Automation of etch pit analyses on solid-state nuclear track detectors with machine learning for laser-driven ion acceleration.

Solid-state nuclear track detectors (SSNTDs) are often used as ion detectors in laser-driven ion acceleration experiments and are considered to be the most reliable ion diagnostics since they are sensitive only to ions and measure ions one by one. However, ion pit analyses require tremendous time and effort in chemical etching, microscope scanning, and ion pit identification by eyes. From a laser-driven ion acceleration experiment, there are typically millions of microscopic images, and it is practically impossible to analyze all of them by hand. This research aims to improve the efficiency and automation of SSNTD analyses for laser-driven ion acceleration. We use two sets of data obtained from calibration experiments with a conventional accelerator where ions with known nuclides and energies are generated and from actual laser experiments using SSNTDs. After chemical etching and scanning the SSNTDs with an optical microscope, we use machine learning to distinguish the ion etch pits from noises. From the results of the calibration experiment, we confirm highly accurate etch-pit detection with machine learning. We are also able to detect etch pits with machine learning from the laser-driven ion acceleration experiment, which is much noisier than calibration experiments. By using machine learning, we successfully identify ion etch pits ∼105 from more than 10 000 microscopic images with a precision of ≳95%. A million microscopic images can be examined with a recent entry-level computer within a day with high precision. Machine learning tremendously reduces the time consumption on ion etch pit analyses detected on SSNTDs.

Associations between body composition and vertebral fracture risk in postmenopausal women.

INTRODUCTION: Osteoporosis is a metabolic bone disease with low bone mineral density (BMD) and high incidence of vertebral fractures (VFs). Postmenopausal women with osteoporosis have decreased total fat and lean mass. This study aimed to investigate the associations between body composition and VF risk and explore the potential predictor of VF risk in postmenopausal women. METHODS: Enrolled 731 postmenopausal women were referred by various departments and outpatient clinics to assess vertebral status between October 2016 and November 2017. The main measures were total body lean mass, fat mass, and BMD. Patients were divided into osteopenia, osteoporosis, and normal groups based on T-scores. Logistic regression analyses were performed to evaluate associations between body composition parameters and VF. RESULTS: VF was significantly associated with increased age, lower height, and lighter weight in all participants, and higher BMI was observed in VF participants. Participants in the osteoporosis group were older and had lower height, weight, and BMD than those in normal and osteopenia groups. Femoral and total hip T-scores as well as T-scores for lumbar spine were significantly lower in participants with VF than in non-VF participants. Percentage of bone mass was also significantly lower in VF participants compared to that of non-VF participants. Women with increased BMD and lower bone mass had reduced odds for VF occurrence. Bone mass was significantly able to identify VF occurrence. CONCLUSIONS: Body composition analysis discerns differences in the bone status of postmenopausal women with and without VF. The cutoff value of the bone mass might be used effectively as an indicator of risk for VF occurrence.

MgZnO/ZnO Two-Dimensional Electron Gas Photodetectors Fabricated by Radio Frequency Sputtering.

MgZnO/ZnO two-dimensional electron gas (2DEG) structures with ZnO annealed at various temperatures (600-900 °C) and photodetectors (PDs) with and without a 2DEG structure were fabricated using a radio frequency magnetron sputtering system. It was found that the carrier concentration and mobility increase with the annealing temperature owing to the improved crystalline in ZnO; however, high-temperature (800 °C or higher) annealing can degrade the crystalline of the ZnO layer. Hall measurements showed that compared with that of bulk ZnO, the sheet carrier concentration of the 2DEG sample increased from 1.3 × 1013 to 1.2 × 1014 cm-2, and the mobility was enhanced from 5.1 to 17.5 cm2/V s. This is because the channel layer is the total thickness (300 nm) in bulk ZnO, whereas the carriers are confined to a 45 nm region beneath the MgZO layer in the 2DEG sample, confirming the 2DEG behavior at the MgZnO/ZnO interface. The PDs with 2DEG structures demonstrate a higher ultraviolet (UV) response and a UV/visible rejection ratio that is six times larger than that of the PDs without a 2DEG structure. The 2DEG structure also induces a photocurrent gain, which results in a 240% quantum efficiency for the 310 nm incident wavelength. The related mechanism is elucidated with a band diagram.

Diagnostic value of apoptosis biomarkers in severe sepsis-A pilot study.

Severe sepsis is associated with significant mortality and massive immune cell lose, or apoptosis. It is unclear whether plasma apoptosis biomarkers could be used as a diagnostic test for severe sepsis. Forty patients with severe sepsis and 35 healthy controls were enrolled. The percentage and apoptosis of monocytes and lymphocytes were detected by flow cytometric analysis. Plasma levels of tumor necrosis factor (TNF)-α, soluble TNF receptor (sTNFR), soluble Fas (sFas), Fas ligand (FasL), caspase-1, and procalcitonin (PCT) were measured. Plasma caspase-1 level was positively correlated with CD4 lymphocyte apoptosis in controls and patients, and with CD8 lymphocyte apoptosis in all subjects. Plasma FasL level was negatively correlated with CD4 and CD8 lymphocyte apoptosis in all subjects. The sFas/FasL ratio was positively correlated with CD4 and CD8 lymphocyte apoptosis and negatively with monocyte apoptosis in all subjects. Compared with PCT, caspase-1, FasL, and sFas/FasL ratio had better negative predictive value and likelihood ratio for a negative test. PCT had better positive predictive value and likelihood ratio for a positive test. This work demonstrated caspase-1, FasL, and sFas/FasL ratio could be candidates for diagnosis of severe sepsis and their diagnostic value was not inferior to that of PCT.

Radiofrequency ablation compared with laparoscopic adrenalectomy for aldosterone-producing adenoma.

BACKGROUND: Radiofrequency ablation (RFA) is an emerging treatment for primary aldosteronism owing to aldosterone-producing adenoma. Whether RFA could be an alternative treatment to laparoscopic adrenalectomy is unknown. METHODS: This was a retrospective comparative study in patients with aldosterone-producing adenoma undergoing either laparoscopic adrenalectomy or CT-guided percutaneous RFA between 2004 and 2012. Short-term outcomes and long-term resolution rates of primary aldosteronism (normalized aldosterone to renin ratio), hypokalaemia and hypertension (BP lower than 140/90 mmHg without antihypertensive medical therapy) were evaluated. RESULTS: Some 63 patients were included, 27 in the laparoscopic adrenalectomy group and 36 in the RFA group. RFA was associated with shorter duration of operation (median 12 versus 124 min; P < 0·001), shorter hospital stay (2 versus 4 days; P < 0·001), lower analgesic requirements (13 of 36 versus 23 of 27 patients; P < 0·001) and earlier resumption of work (median 4 versus 14 days; P = 0·006). Morbidity rates were similar in the two groups. With median follow-up of 5·7 (range 1·9-10·6) years, resolution of primary aldosteronism was seen in 33 of 36 patients treated with RFA and all 27 patients who had laparoscopic adrenalectomy (P = 0·180). Hypertension was resolved less frequently after treatment with RFA compared with laparoscopic adrenalectomy (13 of 36 versus 19 of 27 patients; P = 0·007). Hypokalaemia was resolved in all patients. CONCLUSION: For patients with aldosterone-producing adenoma the efficacy of resolution of primary aldosteronism and hypertension was inferior after treatment with RFA compared with laparoscopic adrenalectomy.

Risk factors for hospital readmission for COPD after implementation of the GOLD guidelines.

BACKGROUND: Few updated studies have investigated risk factors for readmission for chronic obstructive pulmonary disease (COPD) since the implementation of the latest treatment guidelines. OBJECTIVE: To evaluate a series of potential risk factors for readmission in patients with COPD and in a subgroup with very frequent readmissions after implementation of the Global Initiative for Chronic Obstructive Lung Disease guidelines. DESIGN: Two hundred and fifty patients admitted for acute exacerbation of COPD (AECOPD) were recruited over 1 year. The readmission frequency in the ensuing year following hospital discharge was recorded and analysed against potential risk factors collected during the index admission. RESULTS: In the ensuing year, 183 (73.2%) patients were readmitted at least once for AECOPD. Previous non-invasive ventilation for AECOPD (HR 1.56, 95%CI 1.08-2.26), COPD Assessment Test score (HR 1.03, 95%CI 1.00-1.05), 6-minute walk distance (HR 0.98 per 10 m increase, 95%CI 0.97-0.99) and number of admissions for AECOPD in the previous year (HR 1.11, 95%CI 1.06-1.16) were independently associated with time to first readmission. Subgroup analysis showed that anxiety (OR 3.97, 95%CI 1.49-10.57) was strongly associated with very frequent readmissions (⩾4 in 1 year). CONCLUSIONS: AECOPD is associated with high rates of readmission. Anxiety is a potential modifiable factor associated with very frequent readmissions.

Clinical outcomes after spontaneous and nucleos(t)ide analogue-treated HBsAg seroclearance in chronic HBV infection.

BACKGROUND: Both spontaneous and nucleos(t)ide analogue (Nuc)-treated hepatitis B surface antigen (HBsAg) seroclearance are associated with excellent clinical outcomes. AIM: To conduct a case-control study to explore whether there is difference of clinical outcomes between these two groups. METHODS: A total of 312 chronic hepatitis B patients with spontaneous HBsAg seroclearance and 110 patients with Nuc-treated HBsAg seroclearance were recruited retrospectively. Propensity score (PS) matching method produced 98 patients in each group for comparison. The development of hepatocellular carcinoma (HCC), hepatic complications and cumulative incidence of antibody to HBsAg (anti-HBs) was compared. RESULTS: During a mean follow-up period of 107 months after HBsAg seroclearance, five patients developed HCC after a mean period of 75.3 months (four and one patients with spontaneous and Nuc-treated HBsAg seroclearance, respectively) in overall population. One died of pneumonia with sepsis and one experienced variceal bleeding in Nuc-treated patients but none in spontaneous group. The incidence of anti-HBs seroconversion was comparable between spontaneous and Nuc-treated HBsAg seroclearance (69.6% vs. 66.4%, respectively, P = 0.617). There were no significant differences in HCC development (2% vs. 1.1%), overall mortality (0% vs. 1%), variceal bleeding (0% vs. 4.2%) and 6-year cumulative incidence of anti-HBs seroconversion (62.3% vs. 61.5%) among PS-matched patients with spontaneous and Nuc-treated HBsAg seroclearance. CONCLUSIONS: The clinical outcomes between patients with spontaneous and Nuc-treated HBsAg seroclearance are comparable. HCC can develop at a low rate during long-term follow-up and periodic surveillance after HBsAg seroclearance is still mandatory.

CyBorD induction therapy in clinical practice.

Cyclophosphamide, bortezomib and dexamethasone (CyBorD) is a highly active three-drug induction regimen for untreated transplant-eligible multiple myeloma patients. Although CyBorD has been evaluated only in the phase 2 setting in a limited number of patients, its high efficacy and ease of administration have led to its widespread use. Given that clinical trial efficacy can overestimate real-life effectiveness, we reviewed our institutional experience with 109 newly diagnosed patients who were treated with CyBorD in a non-clinical trial setting. After a median of four cycles, overall response rate (ORR) and very good partial response rate or better (⩾VGPR) were 95 and 66%, respectively, comparable to phase 2 studies of CyBorD and other three/four-drug induction regimens. All patients subsequently underwent successful stem cell collection and upgraded responses to ORR 98% and ⩾VGPR 79% post transplant. At a median follow-up of 19.8 months after diagnosis, the 2-year OS probability was 95.3% (95%CI: 89-98). The presence of concurrent plasmacytoma at diagnosis was the only prognostic factor predicting poorer survival (HR=5.56; 95%CI: 0.92-33.74; P=0.03). CyBorD was well-tolerated, with no severe peripheral neuropathy and minimal hematologic toxicity. Therefore, CyBorD is a convenient, well-tolerated, highly effective induction regimen in preparation for autologous SCT in real-life clinical practice.

Hybrid Antegrade Thoracic Aortic Stenting via a Temporary Ascending Aortic Graft Conduit for a Patient with Poor Peripheral Vascular Access.

In patients with poor peripheral vascular access, thoracic aortic stenting procedures can be technically very challenging. Antegrade aortic stent deployments during concomitant open ascending and arch procedures are well described, but the issue of long endovascular catheters and wires may make such an approach difficult and awkward. We describe a novel hybrid method involving a temporary graft conduit to the ascending aorta which is brought caudal toward the foot of the table to facilitate antegrade deployment of the thoracic stent graft.

Basal core promoter mutation is associated with progression to cirrhosis rather than hepatocellular carcinoma in chronic hepatitis B virus infection.

BACKGROUND: As most cases of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) have concurrent cirrhosis, viral factors identified to be associated with HCC might be related to cirrhosis rather than HCC. METHODS: Hepatitis B virus DNA levels, genotypes and precore/basal core promoter (BCP) mutants were compared between cirrhotic HCC and non-cirrhotic HCC patients. Age- and sex-matched case-control studies were performed to identify the risk factors. RESULTS: Hepatitis B virus DNA levels showed no significant difference between non-cirrhotic HCC patients (n=20) and cirrhotic HCC patients (n=140) or 1 : 3 age- and sex-matched cirrhotic HCC patients (n=60), but genotype C and BCP mutant were significantly more prevalent in the latter than in the former. In multiple logistic regression, BCP mutant but not genotype C correlated significantly with the presence of cirrhosis in HCC patients. Compared with inactive carriers (n=60), non-cirrhotic HCC patients (n=20) had significantly higher HBV DNA levels but no difference in HBV genotypes and precore/BCP mutants. Furthermore, HBV DNA levels, the distribution of HBV genotypes and the prevalence of precore/BCP mutants all failed to show any significant difference between cirrhotic HCC patients (n=60) and cirrhotic patients without HCC (n=60). CONCLUSION: Basal core promoter mutant is associated with progression to cirrhosis rather than HCC in chronic HBV infection.

Serial HBV DNA levels in patients with persistently normal transaminase over 10 years following spontaneous HBeAg seroconversion.

Earlier studies addressing the hepatitis B virus (HBV) DNA cut-off level for inactive chronic HBV infection largely involved patients with normal alanine aminotransferase (ALT) for only 1-2 years and based on a single time HBV DNA assay. This study was conducted to address this issue using serial HBV DNA assays in patients with persistently normal ALT (PNALT) over 10 years following spontaneous hepatitis B e antigen (HBeAg) seroconversion. Serial serum specimens (mean 9 samples per patient) of 62 patients with PNALT and no disease progression over 10 years (median 18.1 years) after spontaneous HBeAg seroconversion were assayed for HBV DNA. Excluding assays within 1 year after HBeAg seroconversion, 21% and 82.3% of the patients with PNALT had HBV DNA levels persistently lower than 4 log(10) and 5 log(10) copies/mL, respectively, and only 8% had a level ≥ 5 log(10) copies/mL in at least two assays. Of the 27 patients with PNALT defined by ALT <30 U/L for male and <19 U/L for female, only 33% had serum HBV DNA level persistently <4 log(10) copies/mL. There was no significant difference in the serial HBV DNA changes among patients with different gender, HBV genotype or age at HBeAg seroconversion. Liver biopsy in nine patients invariably showed minimal necroinflammation and one showed Ishak fibrosis score 4. These results suggest that 5 log(10) copies/mL (20,000 IU/mL) is a more appropriate cut-off HBV DNA level for inactive chronic HBV infection in the setting of PNALT.

Appropriate liver resection type for patients with the American joint committee on cancer classification T1 and T2 hepatocellular carcinoma.

SYNOPSIS: Major liver resection prevents intrahepatic tumor recurrence in T2 hepatocellular carcinoma patients with microvascular invasion or daughter nodules. BACKGROUND AND OBJECTIVES: There is no consensus on whether major or minor hepatectomy is better for hepatocellular carcinoma (HCC) patients. We investigated the outcomes of liver resection type in resectable HCC patients. METHODS: Two hundred sixty-three HCC patients with Child-Pugh class A liver function who underwent curative hepatectomy were enrolled. Among them, 186 patients had pathologic stage T1 HCC and 77 had stage T2 HCC. Patients were also classed according to the type of resection (major or minor). Clinicopathologic characteristics and outcomes were compared. RESULTS: Patients with T1 HCC who underwent major resection had a higher rate of blood transfusion than those who underwent minor resection (P < 0.001). The disease-free survival rate of T2 patients who underwent major resection was better than that of patients who underwent minor resection (P = 0.004). The overall survival rates of T1 and T2 HCC patients did not differ significantly between those with major or minor resection. CONCLUSIONS: Major liver resection is recommended for T2 HCC patients with adequate remnant liver function because it results in a better disease-free survival rate than does minor resection in these patients. Minor liver resection is suggested for T1 HCC patients, except for those with a tumor sitting close to vessels, because it is associated with a low incidence of blood transfusion and a good survival rate.

Prevalence and cardiovascular disease risk differences for erectile dysfunction patients by three metabolic syndrome definitions.

There is growing evidence of a link between ED, metabolic syndrome (MS) and cardiovascular disease (CVD). The study was to explore the prevalence of MS using three different definitions (World Health Organization (WHO), International Diabetes Foundation (IDF) and Adult Treatment Panel III (ATP III)), and to compare the association of CVD in ED outpatients using these definitions. This study enrolled 254 participants with a mean age of 55.3 ± 0.9 years (range, 21 to 81 years) with ED as diagnosed by International Index of Erectile Function score. All participants underwent MS evaluation based on the three criteria. Differences of MS prevalence, demographical characteristics, biochemical profiles, pro-inflammatory and inflammatory markers, echocardiographic characteristics and the association with Framingham cardiac risk score (FCRS) were compared. The presence of diabetes mellitus (DM) in the WHO group and high waist girth in the IDF group were significant because of the necessity of respective criteria. The MS prevalence in the WHO, IDF and ATP III groups was 30.7, 34.3 and 36.6%, respectively (P = 0.367). The degrees of agreement among each definition were substantial to perfect. No significant findings in echocardiographic characteristics, biochemical, inflammatory and pro-inflammatory markers were noted. The FCRS showed borderline nonsignificant difference (17.9 ± 0.4, 16.8 ± 0.4 and 16.9 ± 0.4, P = 0.079); however, the FCRS was more closely correlated with the WHO than with the IDF and ATP III (Spearman's correlation coefficients were 0.522, 0.531 and 0.462, respectively; P = 0.021). In patients < 55 years of age and those who smoke, the Spearman's correlation in the WHO group was significantly higher than in the IDF and ATP III groups. The prevalence of the MS using different definitions in ED patients was not different. The WHO-defined MS was more closely associated with CVD.

Pictorial review of mucopolysaccharidosis with emphasis on MRI features of brain and spine.

Mucopolysaccharidosis (MPS) is an inherited metabolic disorder of childhood, characterised by progressive multisystem involvement predominantly affecting the skeletal system leading to skeletal dysplasia. Mental retardation, neuropathy and cardiomyopathy may occur in the most severely affected patients, leading to progressive disability and death in their early third to fourth decades. The purpose of this paper is to illustrate the typical imaging features of different types of MPS, in particular the MR features of the brain and spine in MPS, which are expected to be encountered by radiologists more frequently in their clinical practice as a result of prolonged life expectancy for those with MPS with recent advances in therapeutic interventions. The treatment options and outcomes for MPS patients are also briefly discussed.

Prognostic value of adenosine stress myocardial perfusion by cardiac magnetic resonance imaging in patients with known or suspected coronary artery disease.

BACKGROUND: Cardiac magnetic resonance imaging (CMR) has been intensely researched in recent years, and its high diagnostic accuracy for myocardial ischemia has been demonstrated. However, its prognostic information is very limited. AIM: We sought to assess the value of adenosine stress myocardial perfusion by CMR in predicting cardiac events in patients with known or suspected coronary artery disease (CAD). DESIGN: Retrospective study. METHODS: From January 2003 to December 2008, we retrospectively reviewed consecutive patients with or without history of CAD referred for evaluation of suspected myocardial ischemia who had undergone adenosine stress CMR in our hospital. End points were cardiac death or non-fatal myocardial infarction (MI). RESULTS: After a mean follow-up of 3.2 ± 1.6 years in 203 patients, 15 (7.4%) cardiac events occurred. The 4-year event-free survival was 96.2% for patients with normal stress CMR perfusion and 71.5% for those with abnormal stress CMR perfusion. Univariate analysis showed that both adenosine-induced reversible perfusion defect and delayed gadolinium enhancement by CMR were significant predictors of cardiac events [Hazard ratio (HR) 9.31; 95% Confidence Interval (95% CI) 3.18-27.3; and HR 9.24; 95% CI 3.27-26.08; P < 0.001, respectively). By multivariate analysis, adenosine-induced reversible perfusion defect remained an independent predictor of cardiac events (HR 7.77; 95% CI 2.50-24.18; P < 0.001). In a stepwise multivariate model (Cox regression), an abnormal stress CMR perfusion result had significant incremental predictive value over clinical risk factors and resting regional wall motion abnormality (RWMA) (P < 0.001). CONCLUSION: In patients with known or suspected CAD, adenosine stress CMR could be used to identify patients at high risk for subsequent cardiac death or nonfatal MI. A normal CMR perfusion was associated with a very low long-term event rate and excellent long-term prognosis. In addition, stress CMR perfusion provided important incremental prognostic information over clinical risk factors and RWMA.

Clinical presentations and imaging findings of neuroblastoma beyond abdominal mass and a review of imaging algorithm.

Neuroblastoma is one of the most common malignant neoplasms in childhood. The most common clinical presentation of this tumour is abdominal mass. However, affected children may have various clinical presentations as a result of disseminated metastatic disease or associated paraneoplastic syndromes at the time of diagnosis. In this article we have outlined the imaging findings in seven patients with "extra-abdominal" presentation of neuroblastoma and the pitfalls in making the correct diagnosis. The purpose of this pictorial review is to alert the general radiologist to the possible presentations of this common childhood malignancy to derive early detection and diagnosis.

Prevalence of allergic rhinitis and its associated morbidity in adults with asthma: a multicentre study.

OBJECTIVES: To assess the prevalence of allergic rhinitis in adult patients with asthma in Hong Kong, and to compare the morbidity endured by asthma patients with and without allergic rhinitis. DESIGN: Cross-sectional study. SETTING: Respiratory clinics of four major public hospitals in Hong Kong. PATIENTS: A total of 600 adults with asthma were recruited from March to May 2007. MAIN OUTCOME MEASURES: Doctors and patients completed separate questionnaires evaluating symptoms, treatment, and health care utilisation. Spirometry data were obtained for a subgroup of patients at the time of survey completion. RESULTS: The patients consisted of 267 males and 333 females, with 251 having spirometry data. The mean pre-bronchodilator 1-second forced expiratory volume predicted among those who had spirometry performed was 88% (standard deviation, 28%). In all, 50% of the patients had intermittent and 50% had persistent asthma. Over three quarters (463/600; 77%) of patients had experienced allergic rhinitis symptoms in the past 12 months, of whom 96% had a previous diagnosis of allergic rhinitis. Asthmatics without allergic rhinitis symptoms had higher rates of visits to doctors, pharmacy visits, emergency department attendances, and hospitalisations for asthma than those with both conditions. Among subjects with asthma and allergic rhinitis, those taking nasal steroid (226/463; 49%) had lower rates of emergency department visits (13 vs 25%, P=0.002) and hospitalisations (7 vs 13%, P=0.045) for asthma than those who were not. CONCLUSION: Allergic rhinitis is a common co-morbid condition of asthma in this hospital clinic cohort. Treatment of allergic rhinitis with intra-nasal steroid was associated with less health care utilisation for asthma.