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1.
bioRxiv ; 2024 Apr 18.
Article in English | MEDLINE | ID: mdl-38659928

ABSTRACT

DNA double-strand breaks (DSBs) are nucleolytically processed to generate single-stranded DNA tails for homologous recombination. In Saccharomyces cerevisiae meiosis, this 5'-to-3' resection involves initial nicking by the Mre11-Rad50-Xrs2 complex (MRX) plus Sae2, then exonucleolytic digestion by Exo1. Chromatin remodeling adjacent to meiotic DSBs is thought to be necessary for resection, but the relevant remodeling activity was unknown. Here we show that the SWI/SNF-like ATPase Fun30 plays a major, non-redundant role in resecting meiotic DSBs. A fun30 null mutation shortened resection tract lengths almost as severely as an exo1-nd (nuclease-dead) mutation, and resection was further shortened in the fun30 exo1-nd double mutant. Fun30 associates with chromatin in response to meiotic DSBs, and the constitutive positioning of nucleosomes governs resection endpoint locations in the absence of Fun30. We infer that Fun30 directly promotes both the MRX- and Exo1-dependent steps in resection, possibly by removing nucleosomes from broken chromatids. Moreover, we found that the extremely short resection in the fun30 exo1-nd double mutant is accompanied by compromised interhomolog recombination bias, leading to defects in recombination and chromosome segregation. Thus, this study also provides insight about the minimal resection lengths needed for robust recombination.

2.
J Thorac Oncol ; 18(11): 1492-1503, 2023 11.
Article in English | MEDLINE | ID: mdl-37414358

ABSTRACT

INTRODUCTION: The role of a family history of lung cancer (LCFH) in screening using low-dose computed tomography (LDCT) has not been prospectively investigated with long-term follow-up. METHODS: A multicenter prospective study with up to three rounds of annual LDCT screening was conducted to determine the detection rate of lung cancer (LC) in asymptomatic first- or second-degree relatives of LCFH. RESULTS: From 2007 to 2011, there were 1102 participants enrolled, including 805 and 297 from simplex and multiplex families (MFs), respectively (54.2% women and 70.0% never-smokers). The last follow-up date was May 5, 2021. The overall LC detection rate was 4.5% (50 of 1102). The detection rate in MF was 9.4% (19 of 202) and 4.4% (4 of 91) in never-smokers and in those who smoked, respectively. The corresponding rates for simplex families were 3.7% (21 of 569) and 2.7% (6 of 223), respectively. Of these, 68.0% and 22.0% of cases with stage I and IV diseases, respectively. LC diagnoses within a 3-year interval from the initial screening tend to be younger, have a higher detection rate, and have stage I disease; thereafter, more stage III-IV disease and 66.7% (16 of 24) with negative or semipositive nodules in initial computed tomography scans. Within the 6-year interval, only maternal (modified rate ratio = 4.46, 95% confidence interval: 2.32-8.56) or maternal relative history of LC (modified rate ratio = 5.41, 95% confidence interval: 2.84-10.30) increased the risk of LC. CONCLUSIONS: LCFH is a risk factor for LC and is increased with MF history, among never-smokers, younger adults, and those with maternal relatives with LC. Randomized controlled trials are needed to confirm the mortality benefit of LDCT screening in those with LCFH.


Subject(s)
Lung Neoplasms , Adult , Humans , Female , Male , Lung Neoplasms/diagnostic imaging , Lung Neoplasms/epidemiology , Lung Neoplasms/genetics , Prospective Studies , Early Detection of Cancer/methods , Tomography, X-Ray Computed/methods , Risk Factors , Mass Screening
3.
Diagnostics (Basel) ; 12(12)2022 Dec 16.
Article in English | MEDLINE | ID: mdl-36553201

ABSTRACT

Since excessive alcohol consumption is a shared risk factor for esophageal cancer and liver fibrosis, it is possible that patients with esophageal cancer may develop unknown liver fibrosis or cirrhosis. We applied preoperative transient elastography (TE) to patients without recorded cirrhosis undergoing esophagectomy to clarify the validity in predicting postesophagectomy hepatic failure. The cohort consisted of 107 patients who received TE before esophagectomy between June 2018 and December 2021. Patients were categorized into two groups based on the fibrosis score yielded by preoperative TE (mild group: 0~2, n = 92; severe group: 3~4, n = 15). There was no significant difference in demographic data nor surgical variables between the two groups. None of the cohort encountered hepatic failure, yet the severe fibrosis group had a significantly higher rate of pleural effusion (40.0% versus 15.2%, p = 0.03). The areas under the curve (AUCs) of TE in predicting postoperative complications and 180-day mortality were 0.60 (95% CI: 0.46-0.74) and 0.67 (95% CI: 0.51-0.83), respectively. In conclusion, stratification of patients with esophageal cancer who had liver fibrosis by preoperative TE demonstrates significant validity in predicting postoperative pleural effusions. Recruitment of noncirrhotic patients with higher TE scores is warranted to examine its power in other parameters.

4.
Article in English | MEDLINE | ID: mdl-36232107

ABSTRACT

With decreasing mortality, the quality of life, spiritual needs, and mental health of breast cancer patients have become increasingly important. Demoralization is a poor prognostic factor for cancer patients. The extent of demoralization in breast cancer patients and its association with these factors remains unclear. This cross-sectional study was conducted at a Taiwanese medical center. We enrolled 121 participants (34 with high demoralization and 87 with low demoralization, as per the Mandarin Version of Demoralization Scale). High demoralization was associated with reduced quality of life, sleep quality, and spiritual interests. Multivariate analyses revealed that the scores of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire ≥ 62.5 (OR = 0.21, p = 0.002) and Spiritual Interests Related to Illness Tool Chinese Version ≥ 3.66 (OR = 0.11, p < 0.001) were associated with low demoralization. Demoralized patients with depression had a poorer quality of life and sleep quality. Although not statistically significant, depressed and demoralized participants were at a higher risk of suicide. Cancer patients with both depression and demoralization had the worst prognosis. Breast cancer patients exhibited demoralization when they had unmet bio-psycho-social-spiritual needs. An early assessment of demoralization may improve holistic healthcare for breast cancer patients.


Subject(s)
Breast Neoplasms , Demoralization , Neoplasms , Suicide , Breast Neoplasms/complications , Cross-Sectional Studies , Depression/epidemiology , Depression/psychology , Female , Humans , Inpatients , Neoplasms/psychology , Quality of Life/psychology , Sleep Quality
5.
BMC Surg ; 22(1): 292, 2022 Jul 28.
Article in English | MEDLINE | ID: mdl-35902899

ABSTRACT

BACKGROUND: Esophagectomy remains the standard treatment for esophageal cancer or esophagogastric junction cancer. The stomach, or the gastric conduit, is currently the most commonly used substitute for reconstruction instead of the jejunum or the colon. Preservation of the right gastric and the right gastroepiploic vessels is a vital step to maintain an adequate perfusion of the gastric conduit. Compromise of these vessels, especially the right gastroepiploic artery, might result in ischemia or necrosis of the conduit. Replacement of the gastric conduit with jejunal or colonic interposition is reported when a devastating accident occurs; however, the latter procedure requires a more extensive dissection and multiple anastomosis. CASE PRESENTATION: A 61-year-old male with a lower third esophageal squamous cell carcinoma (cT3N1 M0) who received neoadjuvant chemoradiation with a partial response. He underwent esophagectomy with a gastric conduit reconstruction. However, the right gastroepiploic artery was accidentally transected during harvesting the gastric conduit, and the complication was identified during the pull-up phase. An end-to-end primary anastomosis was performed by the plastic surgeon under microscopy, and perfusion of the conduit was evaluated by the ICG scope, which revealed adequate vascularization of the whole conduit. We continued the reconstruction with the revascularized gastric conduit according to the perfusion test result. Although the patient developed minor postoperative leakage of the esophagogastrostomy, it was controlled with conservative drainage and antibiotic administration. Computed tomography also demonstrated fully enhanced gastric conduit. The patient resumed oral intake smoothly later without complications and was discharged at postoperative day 43. CONCLUSION: Although the incidence of vascular compromise during harvesting of the gastric conduit is rare, the risk of conduit ischemia is worrisome whenever it happens. Regarding to our presented case, with the prompt identification of the injury, expertized vascular reconstruction, and a practical intraoperative evaluation of the perfusion, a restored gastric conduit could be applied for reconstruction instead of converting to more complicated procedures.


Subject(s)
Esophageal Neoplasms , Esophageal Squamous Cell Carcinoma , Anastomosis, Surgical/methods , Esophageal Neoplasms/pathology , Esophageal Neoplasms/surgery , Esophageal Squamous Cell Carcinoma/surgery , Esophagectomy/methods , Esophagogastric Junction/surgery , Humans , Ischemia/surgery , Male , Middle Aged , Perfusion , Stomach/pathology
6.
Health Qual Life Outcomes ; 20(1): 60, 2022 Apr 02.
Article in English | MEDLINE | ID: mdl-35366908

ABSTRACT

BACKGROUND: Demoralization is a common problem in oral cancer patients owing to the chronic and severe nature of their affliction. However, the association between demoralization and the patient's spiritual needs, quality of life, and suicidal ideation remains unclear. This study aims to provide insights into possible links between demoralization among oral cancer patients and its effects on the patient's spiritual needs, quality of life, and suicidal ideation. METHODS: We examined 155 Taiwanese oral cancer inpatients in Taichung Veterans General Hospital, Taiwan, using the following three rating scales: (a) Demoralization Scale Mandarin Version (DS-MV), (b) Spiritual Interests Related to Illness Tool, and (c) The Taiwan Chinese versions of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire. Suicidal ideation was established if at least one of the two suicide-related items on the DS-MV scale were checked. We divided the participants into high- and low-demoralization groups, per the cutoff score of 30. We then explored group associations with sociodemographic features, quality of life, and spiritual needs. Logistic regression and receiver operating characteristic (ROC) curves were used to determine demoralization and its association between these variables. RESULTS: Fifty-five (35.5%) patients were categorized as having high demoralization (DS-MV scale score > 30), with scores for DS-MV for all patients being 27.2 ± 16.8. The rates of suicidal ideation were 29.1% (16/55) in the high-demoralization group and 2% (2/100) in the low-demoralization group, with an odds ratio (95% confidence interval) of 20.10 (4.41-91.55). Logistic regression analysis revealed significant effects of spiritual needs and global health status on the DS-MV scores (p < 0.001). Multivariate analyses further confirmed that only overall quality of life scores < 62.5 and spiritual needs < 3.7 significantly predicted the occurrence of high demoralization. CONCLUSION: High demoralization is associated with low satisfaction with spiritual needs, poor quality of life, and high risk of suicidal ideation. DS-MV may potentially be an effective tool for achieving holistic health care among oral cancer patients.


Subject(s)
Demoralization , Mouth Neoplasms , Cross-Sectional Studies , Humans , Inpatients , Quality of Life , Suicidal Ideation , Surveys and Questionnaires
7.
Diagnostics (Basel) ; 12(2)2022 Jan 29.
Article in English | MEDLINE | ID: mdl-35204438

ABSTRACT

Whole-body computed tomography (WBCT) serves as the first-line imaging modality for breast cancer follow-up. To investigate the imaging characteristics and diagnostic accuracy of WBCT for incidental ovarian tumors in patients with prior breast cancer, we retrospectively reviewed a consecutive cohort of 13,845 patients with breast cancer, of whom 149 had pathologically-proven ovarian lesions. We excluded patients with ovarian diagnosis before breast cancer, CT scan not including ovary, CT-pathology interval >30 days, and severe CT artifact. Among our 60 breast cancer patients (median age, 46 years) with pathologically proven ovarian lesions, 49 patients had benign diseases, seven had primary ovarian cancer and four had ovarian metastasis from breast cancer. The histologic types of breast cancer with ovarian metastases included invasive ductal carcinoma, lobular carcinoma and angiosarcoma. Cystic ovarian lesions identified on WBCT during the breast cancer follow-up are more likely to be benign, while solid-cystic lesions are likely to be primary ovarian cancers, and solid lesions may indicate ovarian metastasis. The diagnostic accuracy, sensitivity, specificity, and areas under the receiver operating characteristic curve of WBCT were 98.3%, 100.0%, 98.0%, and 0.99 (malignant vs. benign); 90.0%, 100.0%, 85.7%, and 0.93 (metastasis vs. primary ovarian cancer), respectively. The only false positive solid lesion was a Sertoli-Leydig tumor. In conclusion, WBCT may help diagnose incidental ovarian tumors in patients with prior breast cancers and guide disease management.

8.
Curr Alzheimer Res ; 19(1): 56-67, 2022.
Article in English | MEDLINE | ID: mdl-35086448

ABSTRACT

BACKGROUND: Vascular Cognitive Impairment, No Dementia (VCIND) is a key stage at which early intervention will delay or prevent dementia. The pathophysiology of VCIND posits that a lesion in a single location in the brain has the ability to disrupt brain networks, and the subsequent abnormal Functional Connectivity (FC) of brain networks leads to deficits in corresponding neurobehavioral domains. In this study, we tested the hypothesis that disrupted anterior cingulate cortex and striatal networks mediated the effects of Physical Activity (PA) on neurobehavioral function. METHODS: In 27 patients with VCIND, FC within the brain networks and neurobehavioral dysfunction were assessed. The relationship between the cognitive scores, FC, and PA was studied. The Fitbit Charge 2 was used to measure step counts, distance, and calories burned. In patients with VCIND, a cross-sectional Spearman's correlation to analyze the relationship among patient-level measures of PA, cognitive function scores, and FC strength within the brain networks. RESULTS: Average step counts and average distance were associated with Trail Making Test B (TMB) time to completion (seconds) and Instrumental Activities of Daily Living (IADL) score (P < 0.05). The average calories burned were associated with IADL score (P = 0.009). The FC within the brain networks anchored by left caudal Anterior Cingulate Cortex (ACC) seeds (x= -5, y= 0, z= 36) and (x= -5, y= -10, z= 47) were positively correlated with average step counts and average distance, were negatively correlated with TMB time to completion (seconds), and were positively correlated with IADL score (P < 0.05). The FC within the brain networks anchored by left subgenual ACC seed (x= -5, y= 25, z= -10) were negatively correlated with average step counts and average distance were positively correlated with TMB time to completion (seconds), and were negatively correlated with IADL score (P < 0.05). The FC within the striatal networks was positively correlated with average calories burned and IADL score (P < 0.05). CONCLUSION: FC within the brain networks anchored by caudal ACC seeds was positively correlated with more average step counts/average distance and better IADL score; negatively correlated with longer TMB time to completion (seconds), whereas FC of subgenual ACC seed was negatively correlated with the same parameters. FC within the brain networks anchored by putamen rather than caudate or pallidum was positively correlated with average calories burned and IADL score.


Subject(s)
Activities of Daily Living , Cognitive Dysfunction , Brain/pathology , Cross-Sectional Studies , Exercise , Humans , Magnetic Resonance Imaging
9.
Ann Thorac Surg ; 113(6): e417-e419, 2022 06.
Article in English | MEDLINE | ID: mdl-34461071

ABSTRACT

Esophageal cancer survival has improved as a result of improvements in surgical techniques and preoperative chemoradiation. Excessive alcohol consumption is a shared risk factor for esophageal cancer and chronic alcoholic pancreatitis. Puestow's procedure is a treatment choice for pain relief and pancreatic duct decompression. It is logical to perform Puestow's procedure in patients undergoing esophagectomy with underlying chronic pancreatitis to preserve pancreatic function and restore quality of life in the setting of improved overall survival of patients with esophageal cancer. This report describes a preliminary experience with 2 patients who underwent both procedures during the same operation and achieved acceptable outcomes.


Subject(s)
Esophageal Neoplasms , Pancreatitis, Chronic , Esophageal Neoplasms/surgery , Humans , Pancreatic Ducts/surgery , Pancreatitis, Chronic/surgery , Quality of Life , Stomach
10.
J Hepatocell Carcinoma ; 8: 937-949, 2021.
Article in English | MEDLINE | ID: mdl-34422707

ABSTRACT

Drug-eluting beads transarterial chemoembolization (DEB-TACE) is an alternative to conventional lipiodol-based TACE (cTACE) to treat hepatocellular carcinoma (HCC). With the advancement in pharmacology, small-caliber DEB-TACE (<100 µm) has been introduced since 2016. For the treatment of hepatic neoplasms or HCC, there is a tendency to use smaller beads by DEB-TACE to achieve more extensive tumor necrosis and a significant reduction in liver toxicity in comparison with that caused by cTACE. However, the indications and potential complications of small-caliber DEB-TACE remain uncertain and have not been well established, due to lack of randomized phase III clinical trials. Instead of systematic or meta-analysis review, this narrative review article describes the suggested indications and contraindications of DEB-TACE with small DEBs, benefit of super-selective embolization of the feeding arteries and the recommended selection of small-caliber DEB. This review was approved by the institutional review board (File Number: 1-105-05-158).

11.
Cancers (Basel) ; 13(16)2021 Aug 05.
Article in English | MEDLINE | ID: mdl-34439100

ABSTRACT

Benign lesions, atypical adenomatous hyperplasia (AAH), and malignancies such as adenocarcinoma in situ (AIS), minimally invasive adenocarcinoma (MIA), and invasive adenocarcinoma (IA) may feature a pure ground-glass nodule (pGGN) on a thin-slide computed tomography (CT) image. According to the World Health Organization (WHO) classification for lung cancer, the prognosis of patients with IA is worse than those with AIS and MIA. It is relatively risky to perform a core needle biopsy of a pGGN less than 2 cm to obtain a reliable pathological diagnosis. The early and adequate management of patients with IA may provide a favorable prognosis. This study aimed to disclose suggestive signs of CT to accurately predict IA among the pGGNs. A total of 181 pGGNs of less than 2 cm, in 171 patients who had preoperative CT-guided localization for surgical excision of a lung nodule between December 2013 and August 2019, were enrolled. All had CT images of 0.625 mm slice thickness during CT-guided intervention to confirm that the nodules were purely ground glass. The clinical data, CT images, and pathological reports of those 171 patients were reviewed. The CT findings of pGGNs including the location, the maximal diameter in the long axis (size-L), the maximal short axis diameter perpendicular to the size-L (size-S), and the mean value of long and short axis diameters (size-M), internal content, shape, interface, margin, lobulation, spiculation, air cavity, vessel relationship, and pleural retraction were recorded and analyzed. The final pathological diagnoses of the 181 pGGNs comprised 29 benign nodules, 14 AAHs, 25 AISs, 55 MIAs, and 58 IAs. Statistical analysis showed that there were significant differences among the aforementioned five groups with respect to size-L, size-S, and size-M (p = 0.029, 0.043, 0.025, respectively). In the univariate analysis, there were significant differences between the invasive adenocarcinomas and the non-invasive adenocarcinomas with respect to the size-L, size-S, size-M, lobulation, and air cavity (p = 0.009, 0.016, 0.008, 0.031, 0.004, respectively) between the invasive adenocarcinomas and the non-invasive adenocarcinomas. The receiver operating characteristic (ROC) curve of size for discriminating invasive adenocarcinoma also revealed similar area under curve (AUC) values among size-L (0.620), size-S (0.614), and size-M (0.623). The cut-off value of 7 mm in size-M had a sensitivity of 50.0% and a specificity of 76.4% for detecting IAs. In the multivariate analysis, the presence of air cavity was a significant predictor of IA (p = 0.042). In conclusion, the possibility of IA is higher in a pGGN when it is associated with a larger size, lobulation, and air cavity. The air cavity is the significant predictor of IA.

12.
Biomed J ; 44(6 Suppl 1): S132-S143, 2021 12.
Article in English | MEDLINE | ID: mdl-35735082

ABSTRACT

BACKGROUND: Quantitative maps from cardiac MRI provide objective information for myocardial tissue. The study aimed to report the T1 and T2∗ relaxation time and its relationship with clinical parameters in healthy Taiwanese participants. METHODS: Ninety-three participants were enrolled between 2014 and 2016 (Males/Females: 43/50; age: 49.7 ± 11.3/49.9 ± 10.3). T1 and T2∗ weighted images were obtained by MOLLI recovery and 3D fully flow compensated gradient echo sequences with a 3T MR scanner, respectively. The T1 map of the myocardium was parcellated into 16 partitions from the American Heart Association. The septal part of basal, mid-cavity, and apical view was selected for the T2∗ map. The difference of quantitative map by sex and age groups were evaluated by Student's TTEST and ANOVA, respectively. The relationship between T1, T2∗ map, and clinical parameters, such as ejection fraction, pulse rate, and blood pressures, were evaluated with partial correlation by controlling BMI and age. RESULTS: Male participants decreased T1 relaxation time in partitions which located in the mid-cavity and apical before 55 years old compared with females (Male/Female: 1143.1.4 ± 72.0-1191.1 ± 37.0/1180.1 ± 54.5-1326.1 ± 113.3 msec, p < 0.01). For female participants, T1 relaxation time was correlated negatively with systolic pressure (p < 0.01) and pulse rate (p < 0.01) before 45 years old. Besides, T1 and T2∗ relaxation time were positively and negatively correlated with ejection fraction and pulse rate after 45 years old in male participants, respectively. Decreased T2∗ relaxation time could be noticed in participants after 45 years old compared with youngers (26.0 ± 6.5/21.9 ± 8.0 msec; 25.2 ± 5.0/21.6 ± 7.2 msec, p < 0.05). CONCLUSION: Reference T1 and T2∗ relaxation time from cardiac MRI in healthy Taiwanese participants were provided with sex and age-dependent manners. The relationship between clinical parameters and T1 or T2∗ relaxation time was also established and could be further investigated for its potential application in healthy/sub-healthy participants.


Subject(s)
Heart/diagnostic imaging , Heart/physiology , Magnetic Resonance Imaging , Adult , Female , Healthy Volunteers , Humans , Male , Middle Aged , Myocardium/pathology , Reproducibility of Results , Ventricular Function, Left
13.
Cancers (Basel) ; 12(8)2020 08 07.
Article in English | MEDLINE | ID: mdl-32784681

ABSTRACT

The purpose of this work was to evaluate the performance of an existing commercially available artificial intelligence (AI) software system in differentiating malignant and benign lung nodules. The AI tool consisted of a vessel-suppression function and a deep-learning-based computer-aided-detection (VS-CAD) analyzer. Fifty patients (32 females, mean age 52 years) with 75 lung nodules (47 malignant and 28 benign) underwent low-dose computed tomography (LDCT) followed by surgical excision and the pathological analysis of their 75 nodules within a 3 month time frame. All 50 cases were then processed by the AI software to generate corresponding VS images and CAD outcomes. All 75 pathologically proven lung nodules were well delineated by vessel-suppressed images. Three (6.4%) of the 47 lung cancer cases, and 11 (39.3%) of the 28 benign nodules were ignored and not detected by the AI without showing a CAD analysis summary. The AI system/radiologists produced a sensitivity and specificity (shown in %) of 93.6/89.4 and 39.3/82.1 in distinguishing malignant from benign nodules, respectively. AI sensitivity was higher than that of radiologists, though not statistically significant (p = 0.712). Specificity obtained by the radiologists was significantly higher than that of the VS-CAD AI (p = 0.003). There was no significant difference between the malignant and benign lesions with respect to age, gender, pure ground-glass pattern, the diameter and location of the nodules, or nodules <6 vs. ≥6 mm. However, more part-solid nodules were proven to be malignant than benign (90.9% vs. 9.1%), and more solid nodules were proven to be benign than malignant (86.7% vs. 13.3%) with statistical significance (p = 0.001 and <0.001, respectively). A larger cohort and prospective study are required to validate the AI performance.

14.
Nature ; 582(7810): 124-128, 2020 06.
Article in English | MEDLINE | ID: mdl-32494071

ABSTRACT

In most species, homologous chromosomes must recombine in order to segregate accurately during meiosis1. Because small chromosomes would be at risk of missegregation if recombination were randomly distributed, the double-strand breaks (DSBs) that initiate recombination are not located arbitrarily2. How the nonrandomness of DSB distributions is controlled is not understood, although several pathways are known to regulate the timing, location and number of DSBs. Meiotic DSBs are generated by Spo11 and accessory DSB proteins, including Rec114 and Mer2, which assemble on chromosomes3-7 and are nearly universal in eukaryotes8-11. Here we demonstrate how Saccharomyces cerevisiae integrates multiple temporally distinct pathways to regulate the binding of Rec114 and Mer2 to chromosomes, thereby controlling the duration of a DSB-competent state. The engagement of homologous chromosomes with each other regulates the dissociation of Rec114 and Mer2 later in prophase I, whereas the timing of replication and the proximity to centromeres or telomeres influence the accumulation of Rec114 and Mer2 early in prophase I. Another early mechanism enhances the binding of Rec114 and Mer2 specifically on the shortest chromosomes, and is subject to selection pressure to maintain the hyperrecombinogenic properties of these chromosomes. Thus, the karyotype of an organism and its risk of meiotic missegregation influence the shape and evolution of its recombination landscape. Our results provide a cohesive view of a multifaceted and evolutionarily constrained system that allocates DSBs to all pairs of homologous chromosomes.


Subject(s)
Chromosomes, Fungal/genetics , Homologous Recombination , Meiosis , Saccharomyces cerevisiae/cytology , Saccharomyces cerevisiae/genetics , Centromere/genetics , Chromosome Segregation , Chromosomes, Fungal/metabolism , DNA Breaks, Double-Stranded , DNA Replication Timing , Meiosis/genetics , Meiotic Prophase I/genetics , Recombinases/metabolism , Saccharomyces cerevisiae Proteins/metabolism , Telomere/genetics , Time Factors
15.
Eur J Radiol ; 128: 109036, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32403031

ABSTRACT

PURPOSE: Myocardial oxygenation imaging is a field-of-interest but its clinical utility largely unexplored. We aimed to investigate the myocardial oxygenation status via T2* imaging and compared with the left ventricular ejection fraction (LVEF) in chronic heart failure (HF) patients after hospitalization. Also, we sought to compare the differences in myocardial oxygenation status among patients with ischemic HF, non-ischemic HF and controls. METHODS: We prospectively enrolled 60 participants, comprising 20 HF patients with LVEF ≥ 50 % as the improved ejection fraction (HFIEF) group, 20 H F patients with ejection fraction <50 % as the reduced ejection fraction (HFREF) group, and 20 controls. Patients were also dichotomized into ischemic and non-ischemic subgroups. T2* values were compared across the study groups, and correlated with LVEF, myocardial scar distribution and quantity. RESULTS: T2* values positively correlated with LVEF and were significantly lower in the HFREF group as compared with both HFIEF and controls (20.06 vs. 24.23; 20.06 vs. 26.32, respectively, both p < 0.05). Lower T2* values were observed in the HFREF group than the HFIEF group and the ischemic subgroup than the non-ischemic subgroup. No significant correlation existed between T2* value and the myocardial scar amounts in ischemic territory. CONCLUSIONS: Oxygen-sensitive T2* measurements showed correlation with LVEF and ischemic etiology in chronic heart failure patients, while the ischemic HFREF patients appeared to be more vulnerable to myocardial oxygen reduction than other groups. T2* measurements may be clinically feasible in monitoring heart failure via myocardial oxygenation and lay the foundation for future studies in prediction heart failure recovery.


Subject(s)
Heart Failure/diagnostic imaging , Heart Failure/etiology , Magnetic Resonance Imaging/methods , Myocardial Ischemia/complications , Myocardial Ischemia/diagnostic imaging , Ventricular Dysfunction, Left/diagnostic imaging , Adult , Aged , Chronic Disease , Female , Heart/diagnostic imaging , Heart/physiopathology , Heart Failure/physiopathology , Hospitalization , Humans , Male , Middle Aged , Myocardial Ischemia/physiopathology , Myocardium/metabolism , Oxygen/metabolism , Prospective Studies , Stroke Volume , Ventricular Dysfunction, Left/complications , Ventricular Dysfunction, Left/physiopathology , Young Adult
16.
J Clin Med ; 9(1)2020 Jan 08.
Article in English | MEDLINE | ID: mdl-31936313

ABSTRACT

BACKGROUND: This prospective study was designed to investigate whether myocardial triglyceride (TG) content from proton magnetic resonance spectroscopy (MRS) and left ventricular (LV) function parameters from cardiovascular magnetic resonance imaging (CMR) can serve as imaging biomarkers in predicting future major cardiovascular adverse events (MACE) and readmission in patients who had been hospitalized for acute heart failure (HF). METHODS: Patients who were discharged after hospitalization for acute HF were prospectively enrolled. On a 3.0 T MR scanner, myocardial TG contents were measured using MRS, and LV parameters (function and mass) were evaluated using cine. The occurrence of MACE and the HF-related readmission served as the endpoints. Independent predictors were identified using univariate and multivariable Cox proportional hazard regression analyses. RESULTS: A total of 133 patients (mean age, 52.4 years) were enrolled. The mean duration of follow-up in surviving patients was 775 days. Baseline LV functional parameters-including ejection fraction, LV end-diastolic volume, LV end-diastolic volume index (LVEDVI), and LV end-systolic volume (p < 0.0001 for all), and myocardial mass (p = 0.010)-were significantly associated with MACE. Multivariable analysis revealed that LVEDVI was the independent predictor for MACE, while myocardial mass was the independent predictor for 3- and 12-month readmission. Myocardial TG content (lipid resonances δ 1.6 ppm) was significantly associated with readmission in patients with ischemic heart disease. CONCLUSIONS: LVEDVI and myocardial mass are potential imaging biomarkers that independently predict MACE and readmission, respectively, in patients discharged after hospitalization for acute HF. Myocardial TG predicts readmission in patients with a history of ischemic heart disease.

17.
J Cardiovasc Magn Reson ; 18: 9, 2016 Feb 05.
Article in English | MEDLINE | ID: mdl-26850626

ABSTRACT

BACKGROUND: Increased myocardial triglyceride (TG) content has been recognized as a risk factor for cardiovascular disease. However, its relation with cardiac function in patients on recovery from acute heart failure (HF) remains unclear. In this cross-sectional study, we sought to investigate the association between myocardial TG content measured on magnetic resonance spectroscopy ((1)H-MRS) and left ventricular (LV) function assessed on cardiovascular magnetic resonance (CMR) in patients who were hospitalized with HF. METHODS: A total of 50 patients who were discharged after hospitalization for acute HF and 21 age- and sex-matched controls were included in the study. Myocardial TG content and LV parameters (function and mass) were measured on a 3.0 T MR scanner. Fatty acid (FA) and unsaturated fatty acid (UFA) content was normalized against water (W) using the LC-Model algorithm. The patient population was dichotomized according to the left ventricular ejection fraction (LVEF, <50% or ≥ 50%). RESULTS: H-MRS data were available for 48 patients and 21 controls. Of the 48 patients, 25 had a LVEF <50% (mean, 31.2%), whereas the remaining 23 had a normal LVEF (mean, 60.2%). Myocardial UFA/W ratio was found to differ significantly in patients with low LVEF, normal LVEF, and controls (0.79% vs. 0.21% vs. 0.14%, respectively, p = 0.02). The myocardial UFA/TG ratio was associated with LV mass (r = 0.39, p < 0.001) and modestly related to LV end-diastolic volume (LVEDV; r = 0.24, p = 0.039). We also identified negative correlations of the myocardial FA/TG ratio with both LV mass (r = -0.39, p < 0.001) and LVEDV (r = -0.24, p = 0.039). CONCLUSIONS: As compared with controls, patients who were discharged after hospitalization for acute HF had increased myocardial UFA content; furthermore, UFA was inversely related with LVEF, LV mass and, to a lesser extent, LVEDV. Our study may stimulate further research on the measure of myocardial UFA content by (1)H-MRS for outcome prediction. TRIAL REGISTRATION: ClinicalTrial.gov: NCT02378402 . Registered 27/02/2015.


Subject(s)
Heart Failure/diagnosis , Magnetic Resonance Imaging, Cine , Myocardium/chemistry , Proton Magnetic Resonance Spectroscopy , Triglycerides/analysis , Ventricular Function, Left , Acute Disease , Algorithms , Biomarkers/analysis , Case-Control Studies , Cross-Sectional Studies , Fatty Acids, Unsaturated/analysis , Female , Heart Failure/metabolism , Heart Failure/physiopathology , Hospitalization , Humans , Image Interpretation, Computer-Assisted , Male , Middle Aged , Predictive Value of Tests , Prognosis , Stroke Volume , Systole
18.
Ultrason Imaging ; 35(1): 3-16, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23287503

ABSTRACT

Quantization is a necessary step in a digital beamformer that should be implemented efficiently when designing an ultrasound imaging system. Several factors should be considered, including the accuracy of both amplitude and phase in the digital representation, the quantization efficiency, and the complexity of the quantization scheme. While uniform scalar quantization (SQ) is currently used in most ultrasound imaging systems, this study used simulations and experimental data to explore vector quantization (VQ) based on the signals received by adjacent elements of the transducer array generally being strongly correlated. The signal-to-quantization-noise ratio, focusing quality, and accuracy in phase aberration correction and blood velocity estimation were assessed. The results show that using VQ instead of conventional SQ reduces the quantization noise by 10 dB with minimal degradation in the focusing quality. Similarly, the performance of correlation-based phase aberration correction was not affected at this level of quantization. Nevertheless, velocity estimation accuracy was found to be more susceptible to VQ noise when the reduction in the number of bits is limited to a factor of two. One benefit of using a more efficient quantizer is the reduced data size, which directly affects the data transfer rate and is an important design consideration for a digital imaging system.


Subject(s)
Image Processing, Computer-Assisted/methods , Signal-To-Noise Ratio , Ultrasonography/methods , Humans , Signal Processing, Computer-Assisted , Ultrasonography, Doppler
19.
Chang Gung Med J ; 34(1): 75-83, 2011.
Article in English | MEDLINE | ID: mdl-21392477

ABSTRACT

BACKGROUND: The aim of this study was to assess the diagnostic performance of stereotactic core needle breast biopsy using spring-loaded or vacuum-assisted techniques for impalpable microcalcification lesions in Taiwanese women. METHODS: We retrospectively reviewed the data of patients who received stereotactic core needle breast biopsy for impalpable mammographic microcalcification lesions from January 1999 to February 2009. The accuracy, false negative rate, ductal carcinoma in situ (DCIS) upgrade rate and rate of concordance with biopsy procedures were determined. We also compared the diagnostic performance between the vacuum-assisted and spring-loaded techniques. RESULTS: A total of 335 breast stereotactic core needle biopsy procedures (218 by spring-loaded and 117 by vacuum-assisted technique) were enrolled for analysis. The overall accuracy, false negative rate, DCIS upgrade rate and concordance rate with stereotactic core needle biopsy were 88.5%, 17.3%, 23.1% and 83.8% respectively. The vacuum-assisted technique yielded better results than the spring-loaded technique in accuracy (100% vs. 84%), and the false negative (7.1% vs. 21%), DCIS upgrade (0% vs. 37.5%), and concordance rates (95% vs. 79.6%). CONCLUSION: Stereotactic core needle biopsy is a feasible technique in diagnosing impalpable microcalcification lesions of the breast in Taiwanese women. The diagnostic performance of the vacuum-assisted technique was better than that of the spring-loaded technique.


Subject(s)
Biopsy, Needle/methods , Breast Diseases/pathology , Breast/pathology , Calcinosis/pathology , Stereotaxic Techniques , Adult , Aged , Breast Neoplasms/pathology , Carcinoma, Intraductal, Noninfiltrating/pathology , China , Female , Humans , Middle Aged , Retrospective Studies , Vacuum
20.
Ultrasound Med Biol ; 36(9): 1431-6, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20800170

ABSTRACT

This study attempts to identify factors that influence the success or failure of subclassifying 154 cases of neck lymphoma by ultrasound-guided core needle biopsy (UGCNB). Variables including age, gender, nodal size, cutting needle bore, number of core tissues obtained, presence of nodal necrosis or infarct, fragmentation of the specimens and subclassification of lymphoma were reviewed and statistically analyzed to check if they were related to the success of UGCNB. UGCNB was successful in subclassifying lymphoma in 138 (89.7%) cases, in diagnosing lymphoma in 11 (7.1%) and unsuccessful in diagnosing lymphoma in five (3.2%) cases. No complications were encountered. The factors leading to failure in subclassification included the presence of composite lymphoma (p = 0.001), nodal necrosis or infarct (p = 0.001) and insufficiency or fragmentation of the specimens (p < 0.001). UGCNB is a safe and efficient procedure in subclassifying lymphoma. It may obviate surgical biopsy in 89.7% of cases.


Subject(s)
Diagnostic Errors , Head and Neck Neoplasms/diagnostic imaging , Lymphatic Diseases/diagnostic imaging , Lymphoma/diagnostic imaging , Adolescent , Adult , Aged , Aged, 80 and over , Biopsy, Needle , Child , Female , Follow-Up Studies , Head and Neck Neoplasms/classification , Head and Neck Neoplasms/diagnosis , Humans , Immunohistochemistry , Lymphoma/classification , Lymphoma/diagnosis , Male , Middle Aged , Ultrasonography
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