Functional activation of pyruvate dehydrogenase in human brain using hyperpolarized [1-13 C]pyruvate

PURPOSE

Pyruvate, produced from either glucose, glycogen, or lactate, is the dominant precursor of cerebral oxidative metabolism. Pyruvate dehydrogenase (PDH) flux is a direct measure of cerebral mitochondrial function and metabolism. Detection of [13 C]bicarbonate in the brain from hyperpolarized [1-13 C]pyruvate using carbon-13 (13 C) MRI provides a unique opportunity for assessing PDH flux in vivo. This study is to assess changes in cerebral PDH flux in response to visual stimuli using in vivo 13 C MRS with hyperpolarized [1-13 C]pyruvate.

METHODS

From seven sedentary adults in good general health, time-resolved [13 C]bicarbonate production was measured in the brain using 90° flip angles with minimal perturbation of its precursors, [1-13 C]pyruvate and [1-13 C]lactate, to test the hypothesis that the appearance of [13 C]bicarbonate signals in the brain reflects the metabolic changes associated with neuronal activation. With a separate group of healthy participants (n = 3), the likelihood of the bolus-injected [1-13 C]pyruvate being converted to [1-13 C]lactate prior to decarboxylation was investigated by measuring [13 C]bicarbonate production with and without [1-13 C]lactate saturation.

RESULTS

In the course of visual stimulation, the measured [13 C]bicarbonate signal normalized to the total 13 C signal in the visual cortex increased by 17.1% ± 15.9% (p = 0.017), whereas no significant change was detected in [1-13 C]lactate. Proton BOLD fMRI confirmed the regional activation in the visual cortex with the stimuli. Lactate saturation decreased bicarbonate-to-pyruvate ratio by 44.4% ± 9.3% (p < 0.01).

CONCLUSION

We demonstrated the utility of 13 C MRS with hyperpolarized [1-13 C]pyruvate for assessing the activation of cerebral PDH flux via the detection of [13 C]bicarbonate production.

Pneumonitis After Concurrent Chemoradiation and Immune Checkpoint Inhibition in Patients with Locally Advanced Non-small Cell Lung Cancer

AIMS

Pneumonitis is a common and potentially deadly complication of combined chemoradiation and immune checkpoint inhibition (CRT-ICI) in patients with locally advanced non-small cell lung cancer (LA-NSCLC). In this study we sought to identify the risk factors for pneumonitis with CRT-ICI therapy in LA-NSCLC cases and determine its impact on survival.

MATERIALS AND METHODS

We conducted a retrospective chart review of 140 patients with LA-NSCLC who underwent curative-intent CRT-ICI with durvalumab between 2018 and 2021. Pneumonitis was diagnosed by a multidisciplinary team of clinical experts. We used multivariable cause-specific hazard models to identify risk factors associated with grade ≥2 pneumonitis. We constructed multivariable Cox proportional hazard models to investigate the impact of pneumonitis on all-cause mortality.

RESULTS

The median age of the cohort was 67 years; most patients were current or former smokers (86%). The cumulative incidence of grade ≥2 pneumonitis was 23%. Among survivors, 25/28 patients had persistent parenchymal scarring. In multivariable analyses, the mean lung dose (hazard ratio 1.14 per Gy, 95% confidence interval 1.03-1.25) and interstitial lung disease (hazard ratio 3.8, 95% confidence interval 1.3-11.0) increased the risk for pneumonitis. In adjusted models, grade ≥2 pneumonitis (hazard ratio 2.5, 95% confidence interval 1.0-6.2, P = 0.049) and high-grade (≥3) pneumonitis (hazard ratio 8.3, 95% confidence interval 3.0-23.0, P < 0.001) were associated with higher all-cause mortality.

CONCLUSIONS

Risk factors for pneumonitis in LA-NSCLC patients undergoing CRT-ICI include the mean radiation dose to the lung and pre-treatment interstitial lung disease. Although most cases are not fatal, pneumonitis in this setting is associated with markedly increased mortality.

Feasibility and Clinical Implementation of Electron FLASH Radiation Therapy in the Yorkshire Swine Model

PURPOSE/OBJECTIVE(S)

Preclinical studies have shown FLASH radiation therapy (RT) increases the therapeutic index through reduction in normal tissue toxicity but with retained tumor control compared to conventional dose rate (CONV) RT. Dosimetry in FLASH beams is challenging and complex as beam monitoring and proper dosimetry analysis remain uncertain and under investigation. Despite these limitations, clinical translation of FLASH RT has already begun. For translation of FLASH RT from the preclinical stage, it is critical that robust clinical workflows and dosimetry methods be confidently established to ensure patient safety. Here, we present the clinical workflow for the Yorkshire pig, an animal that resembles the body dimension, weight, and biology of a human patient, with the goal to establish standard operating procedures to ensure a safe and robust clinical translation in our upcoming phase I study in cutaneous tumors. The study determines feasibility and safety while finding incidence of dose-limiting toxicities and maximum tolerable dose for future Phase II trials.

MATERIALS/METHODS

All procedures were approved by the institutional animal care and use committee. 6 pigs (40-50 kg) were placed under general anesthesia and underwent CT imaging for radiation therapy simulation purposes. The skin was first shaven, and targets on the dorsolateral flanks were marked with tattoos and BBs for CT visualization. Vacloc immobilization was used to allow for reproducible setup on the treatment couch. A treatment planning model was established for treatment planning and dose evaluation purposes. CONV and FLASH single and fractionated dose regimens were prescribed to the 90% isodose line in a 9 MeV beam. Skin collimation and bolus minimized beam penumbra and increased skin dose. Treatment time and pulse repetition frequency were constant between all FLASH fields. Prescription levels were varied via dose per pulse. Calibration and verification of these settings were performed utilizing a multi-dosimeter method for verification in solid water. Output of the beam was verified on the day of the treatment using beam current transformers. This same multi-dosimeter method was used as in-vivo dosimetry on treatment day and compared to the dose verification ensure full dose was received.

RESULTS

Variation between the three dosimeter methods was found to be within 5% among all pigs within the study. The maximum percent difference between dose verification and dose delivery was 6%. Consideration must be taken in dosimeter readout error due to the surface of the pig skin. FLASH and CONV toxicity results are currently under evaluation and will be published upon completion of the study.

CONCLUSION

Establishing guidelines and protocols for electron FLASH clinical translation is important to instill confidence in patient safety with this new technique. This study has further optimized and developed dosimetry tools and setup to be used in future clinical trials.

Long-Term Outcomes and Toxicity in Esophageal Cancer Patients after Neoadjuvant or Definitive Concurrent Chemotherapy with Proton Beam Therapy

PURPOSE/OBJECTIVE(S)

Proton-beam therapy (PT) is increasingly utilized over three dimensional-conformal radiation therapy (3D-CRT) and intensity modulated radiation therapy (IMRT) photon irradiation for the treatment of various malignancies due to better toxicity reduction. We investigated the long-term outcomes and toxicity in esophageal cancer (EC) patients treated with PT as part of their neoadjuvant concurrent chemoradiation followed by surgery (nCRT) or definitive concurrent chemoradiation (dCRT) treatment regimen.

MATERIALS/METHODS

All consecutively treated, American Joint Committee on Cancer 7th edition clinical stage I-IV EC patients from 2006 to 2022 were retrospectively analyzed. Standard RT dose for most patients was 50.4 Gy/28 fractions. nCRT patients had surgery within 4 months post-RT. Kaplan-Meier method was used to determine overall survival (OS), locoregional recurrence-free survival (LRRFS) and distant metastatic-free survival (DMFS). Acute and chronic RT-related toxicities were graded with Common Terminology Criteria for Adverse Events version 4.0.

RESULTS

There were 510 EC PT patients: 204 (40%) had nCRT and 306 (60%) had dCRT. Most lesions were located in the lower esophagus, of adenocarcinoma histology and treated with passive scatter PT. Overall median follow-up was 72 months. Median, 3- and 5-year OS for all patients were 43 months, 54.1% and 44.9%, respectively. Median LRRFS and DMFS were not reached. Esophagitis was the most common grade ≥3 (G3+) toxicity (59 patients; 28.9%, including a G4 and a G5 toxicity), followed by nausea (29 patients; 14.2%) and esophageal stricture (26 patients, 12.7%). With nCRT, median, 3- and 5-year OS were 80 months, 64.7% and 56.1%, respectively, while the median LRRFS and DMFS were not reached again. Their most common G3+ toxicity was esophagitis in 14 patients (6.9%) followed by nausea (8 patients; 3.9%). An nCRT patient developed G4 RT pneumonitis. Pathological complete response (pCR) was observed in 58 patients (28.4%). Surgery-related pulmonary, cardiac and gastrointestinal complications were reported in 38 (18.6%), 40 (19.6%) and 43 (21.1%) patients, respectively. dCRT patients had a median follow-up of 65 months, and median, 3- and 5-year OS of 32 months, 46.7% and 37.0%, respectively. Although the median LRRFS was not reached, the median DMFS was 74 months. The most observed dCRT G3+ toxicity was esophagitis (45 patients, 22.1%: including both G4 and G5 patients) and then esophageal stricture (23 patients, 11.3%). A dCRT patient developed G4 fistula.

CONCLUSION

To our knowledge, this is the largest single-institutional study on EC long-term outcomes and toxicity using PT. Our cohort reveals good outcomes and mostly mild CRT-related toxicities. Trimodality nCRT with protons demonstrates excellent outcomes relative to the CROSS trial (49.4 months) with identical pCR rate (29% in CROSS) and similar toxicity profile. nCRT with protons should be studied rigorously in the current randomized phase III trial NRG GI006.

Comparing 90-Day Post-Operative Mortality after Neoadjuvant Proton-Based vs. Photon-Based Chemoradiotherapy for Esophageal Cancer

PURPOSE/OBJECTIVE(S)

Standard of treatment for locally advanced esophageal cancer consists of chemoradiotherapy (CRT) followed by surgery. Evidence suggests that proton beam therapy (PBT) results in lower toxicity and fewer post-operative complications compared to photon-based radiotherapy (RT). Mortality in the first 90 days after surgery is a rare event occurring in 2-8% of patients, with higher reported rates (of up to 17%) in older patients. This 90-day mortality (90DM) rate is an important measure of post-operative (non-oncologic) mortality as a proxy of quality of care. We hypothesize that PBT could reduce the incidence of 90DM compared to photon-based RT.

MATERIALS/METHODS

From a single-center retrospectively acquired database patients with esophageal cancer treated with neoadjuvant CRT and esophagectomy in 1998-2022 were selected. Univariable logistic regression analyses were used to study the associations of RT modality and other patient- and treatment-related characteristics with 90DM. Subsequently, 3 separate methods were applied to adjust for confounding bias. These included multivariable logistic regression, 1:1 nearest-neighbor propensity score matching (PSM), and inverse probability of treatment weighting (IPTW). Finally, stratified analyses for patient groups aged ≥67 vs. <67 years were performed.

RESULTS

A total of 894 eligible patients were included (PBT, n = 202; photon-based RT, n = 692). PBT patients had a significantly higher age, better performance score, and a higher number of comorbidities. The 90DM rate was 5 (2.5%) in the PBT group and 29 (4.2%) in the photon-based RT group (p = 0.262). Significant univariable predictors of 90DM included higher age and tumor location. After multivariable adjustment, PBT vs. photon therapy was not significantly associated with 90DM (OR 0.49, 95% CI 0.18-1.31). The 90DM rates in the PSM cohort (n = 181 vs. n = 181) were 2.8% for PBT and 3.3% for photon-based RT (p = 0.379). The 90DM rates in the IPTW cohort were 2.8% for PBT and 4.1% for photon-based RT (p = 0.427). In the full cohort, stratified analysis for age groups revealed that in patients aged ≥67 years, PBT was associated with a decreased risk of 90DM compared to photon-based RT (1.3% vs. 8.8%; p = 0.046), which was not the case in patients aged <67 years. In the PSM cohort, a comparable (but non-significant) difference was observed in favor of PBT in patients aged ≥67 years (i.e., 1.5% vs. 7.5%; p = 0.099). Within-group analyses in the original cohort demonstrated that a higher age significantly increased the risk of 90DM within the photon-based RT group (8.8% vs. 2.7% for age ≥67 vs. <67 years; p = 0.001), but not within the PBT group (1.3% vs. 3.2%; p = 0.398).

CONCLUSION

Post-operative 90DM after esophagectomy for cancer was not significantly different between PBT and photon-based neoadjuvant CRT. However, among older patients we observed a signal that PBT may reduce the risk of 90DM. Higher age increased the risk of 90DM in patients who underwent photon-based RT, but not in patients who underwent PBT.

Prospective Trial of Using Imaging to Predict Pathologic Response and Clinical Outcomes in Locally Advanced Esophageal Cancer

PURPOSE/OBJECTIVE(S)

Trimodality therapy with chemoradiation (CRT) followed by esophagectomy is the standard of care for locally advanced esophageal cancer. An unresolved question is whether pathologic complete response (pCR) can be assessed non-invasively for patients post-CRT. In this study, we assessed whether diffusion-weighted imaging (DWI) with MRI or PET can be used as predictors of pCR and other clinical outcomes after CRT.

MATERIALS/METHODS

Patients were enrolled on a single-arm institutional trial (PA13-0380) assessing the role of imaging in predicting outcomes in potentially resectable esophageal patients undergoing trimodality therapy. All patients received neoadjuvant CRT, and 29 patients had subsequent surgery. DWI MRI and PET scans were obtained at baseline, 2 weeks after the start of CRT (interim) and 4 to 6 weeks after completion of CRT (follow up). Apparent diffusion coefficients (ADCs) were calculated based on DWI images. Circulating tumor DNA was obtained for 27 patients post-radiation using CAPP-Seq. Mann-Whitney tests compared imaging changes associated with pCR. Discrimination of pCR by imaging changes was quantified by received operating characteristics. Youden's index was applied to select optimal thresholds. Kaplan-Meier analysis was performed to assess differences in overall survival (OS) and progression-free survival (PFS) by changes in DWI, PET, and ctDNA parameters.

RESULTS

Our cohort of 60 patients had a median follow up of 42.7 months, age of 65.4 yrs, and ECOG of 1 at completion of CRT. 90% were male, 58% had a history of smoking, and 85% were white. 83% had adenocarcinoma with the rest squamous cell carcinoma. Stages of the patients ranged from IIA to IIIB. All had moderately (47%) or poorly (53%) differentiated disease. All received 41.4-50.4 Gy in 1.8 Gy fractions with the majority receiving 50.4 Gy (95%). 29 patients underwent surgery after CRT of which 8 (27.6%) had pCR. Mean ΔADC from baseline to mid-treatment was most associated with pCR (AUC = 0.98, p<0.001) for patients undergoing surgery. Max ΔADC from baseline to first follow-up was most associated with OS (p = 0.002) and PFS (p<0.001) for the whole cohort. 27 patients had ctDNA analyzed after RT with the presence of ctDNA significantly associated with worse OS (HR = 0.12, p = 0.05) and PFS (HR = 0.10, p = 0.002). Combining ctDNA and max ΔADC generated a model that was more predictive of OS and PFS than either alone. We found that neither the PET parameters of TLG or SUV max at baseline or changes in these parameters from baseline to mid-treatment or first follow-up were as predictive as DWI.

CONCLUSION

We show that changes in DWI is associated with pCR, OS, and PFS in resectable esophageal cancer patients undergoing CRT. DWI was more predictive than PET and a model combining DWI and ctDNA was the most predictive of clinical outcomes. This study shows the significant promise of using DWI in potentially guiding treatment decisions in esophageal cancer patients and will require validation in a larger cohort.

Subacute Cutaneous Toxicity with Single-Fraction Electron FLASH RT in Yorkshire Swine

PURPOSE/OBJECTIVE(S)

Information regarding acute/subacute skin toxicity of electron FLASH radiation therapy (RT) is limited. We evaluated short-term safety of electron FLASH for human trials by investigating subacute toxicity compared to conventional dose-rate RT (CONV) in the Yorkshire pig, an animal model known to closely approximate human skin and routinely used for toxicity studies.

MATERIALS/METHODS

Two healthy 50 kg pigs underwent CT imaging for RT treatment planning with field visualization via BBs and tattoos on each dorsolateral flank. Each target received a single fraction of 20, 25 or 30 Gy with FLASH and CONV on opposing sides delivered using a dedicated mobile linear accelerator. FLASH dose rates ranged from 164-245 Gy/sec (12 pulses delivered over 0.122 sec) while the CONV dose rate was set at 0.18 Gy/sec. Doses were verified using thermo- and optically stimulated luminescent dosimeters, and Gafchromic films. We obtained baseline and weekly images up to 98 days post-RT (D98) for blinded toxicity grading by 3 expert radiation oncologists using the modified RTOG radiation dermatitis (RD) scale. We measured erythema and pigmentation indices on those timepoints using a handheld spectrophotometer. We also obtained punch biopsies of targets and non-irradiated controls on D10 and D30 for RNA sequencing and two 6-marker multiplex immunofluorescence analyses of inflammation, immune response, and fibrosis. FLASH and CONV data were compared using repeated measures ANOVA and transcriptomic analyses using DESeq2.

RESULTS

All RT targets developed peak median grade 4 (ulceration, hemorrhage, or necrosis) RD by D84 regardless of FLASH or CONV delivery. However, FLASH targets developed peak RD later than CONV targets after 20 Gy (D84 vs D63), 25 Gy (D84 vs D49) and 30 Gy (D63 vs D42). FLASH induced qualitatively lower mean pigmentation and erythema indices than CONV for all 3 doses. Similarly, peak mean pigmentation indices occurred later with FLASH vs CONV for 20 Gy (D84 vs D63), 25 Gy (D84 vs D49) and 30 Gy (D77 vs D63). However, peak mean erythema indices occurred on the same day for FLASH and CONV (D63 for 20 Gy and D42 for 25 and 30 Gy). Transcriptomic analyses revealed significantly upregulated signals for wound healing (including TGF-beta, cell adhesion and extracellular matrix receptor interaction) and leukocyte infiltration with 20 Gy CONV mostly by D10, while FLASH upregulated those pathways only after 25 or 30 Gy, or by D30, or never at all. Preliminary immunofluorescence data showed FLASH may induce less T cell infiltrate and TGF-beta-expressing macrophages than CONV.

CONCLUSION

Single-fraction electron FLASH resulted in delayed onsets of both subacute cutaneous toxicity and wound healing with leukocytic infiltration signaling than dose-matched CONV based on both subjective and objective metrics of skin injury. Our findings suggest further investigations of optimal dose of electron FLASH for safe clinical translation is warranted, and we have a dose-finding study currently underway.

Legacy effects of infection in patients with heart failure: a national cohort study of 31,318 patients in Taiwan

Background

Although infection is a common cause of hospitalization in patients (pts) with heart failure (HF), the long-term cardiovascular (CV) prognosis in HF after infection is not well studied.

Methods and results

From 2009 to 2015, 310,485 pts with their first HF admissions and survival to discharge were identified from the National Health Insurance Research Database. Among the pts, 103,505 (33.3%) were readmitted within 1 year after HF discharge for infection, including pneumonia (44.2%), urinary tract infection (UTI) (37.9%), skin and soft tissue infections (9.7%), and others (8.1%). Those without admission for any infection were controls. We compared the primary composite endpoint, including all-cause death, acute myocardial infarction (AMI), stroke, and hospitalization for HF (HHF) between the 2 groups after the infection episode. After propensity score matching, the clinical characteristics (age 71.7±13.9 years, male 52.0%) and treatment were similar between the groups (n=15,659 in each group). In a mean follow-up time of 4.3±2.9 years, 86.2% pts with a history of infection admission and 63.6% pts in the control group met the primary endpoint. Multivariate Cox proportional hazards analysis showed the infection group had a higher risk of the primary composite endpoint (HR 1.760, 95% CI 1.714–1.807), including all-cause death (HR 1.587, 95% CI: 1.540–1.636), HHF (HR 1.993, 95% CI 1.922–2.066), AMI (HR 1.332, 95% CI 1.224–1.450), and stroke (HR 1.769, 95% CI 1.664–1.882). In infection group, HHF was the earliest outcome event with a mean time of 17.5 months and mortality is the second early event with a mean time of 23 months after discharge from the infection episode. Pneumonia carried a higher risk than UTI for the primary composite endpoint (HR 1.140, 95% CI 1.104–1.178).

Conclusions

One-third of HF pts discharged from the hospital experienced acute infection that required readmission. The pts had worse CV prognosis after readmission for infectious disease compared to those without infection

Funding Acknowledgement

Type of funding sources: Private hospital(s). Main funding source(s): This study is supported by National Cheng Kung University Hospital and Tainan Hospital, Ministry of Health and Welfare, Taiwan.

[Association between periodontitis and mild cognitive impairment: a clinical pilot study]

Objective: To evaluate the association between periodontitis and mild cognitive impairment (MCI), and explore the potential local oral risk factors for MCI. Methods: The study included 70 middle-aged and elderly subjects (44 females and 26 males) with periodontal disease who were first diagnosed by the Department of Periodontology or referred by the Department of Geriatrics in Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine from January 2021 to January 2022. In this study, the control group consisted of periodontal disease patients without cognitive impairment, and the case group (MCI group) consisted of those diagnosed with MCI referred by the geriatrics specialists. Full-mouth periodontal examinations of all subjects were performed and periodontal indicators were recorded by periodontists, while digital panoramic radiographs were taken. The severity of periodontitis was defined according to the 1999 classification, and the staging and grading of periodontitis were defined according to the 2018 American Academy of Periodontology and European Federation of Periodontology classification. The mini-mental state examination scale was chosen by geriatricians to evaluate the cognitive function of the included subjects. The cubital venous blood was drawn to detect the expression levels of inflammatory factors such as hypersensitive C-reactive protein (hs-CRP), interleukin (IL)-1β, IL-6 and tumor necrosis factor-α(TNF-α) in serum. Independent-samples t test and chi-square test were used to analyze the differences in population factors, periodontal-related indexes and serum inflammatory factors between the two groups (α=0.05). Odds ratios (OR) for MCI according to the severity of periodontitis and main periodontal clinical indexes were calculated by binary Logistic analysis. Results: Thirty-nine subjects were included in the control group and thirty-one in the MCI group. The age of the study population was (58.3±6.2) years (range: 45-70 years). The comparison between two groups showed that the control group was with higher educational background (χ²=9.45, P=0.024) and 2.6 years younger than the MCI group [(57.1±6.0) years vs. (59.7±6.3) years, t=-1.24, P=0.082]. The number and proportion of moderate to severe periodontitis in control group were significantly lower compared to those in MCI group (17 cases with 43.6% vs. 23 cases with 74.2%, χ²=6.61, P=0.010), and the OR of moderate to severe periodontitis adjusted by age and educational background was 3.00 (95%CI: 1.01-8.86, P=0.048). Compared with the grading (χ²=5.56, P=0.062) of periodontitis, staging had a greater impact on MCI (χ²=7.69, P=0.041), moreover the proportion of MCI in stage Ⅰ grade A periodontitis was significantly lower than any other type of periodontitis (χ²=13.86, P=0.036). In addition, less presence of deep periodontal pockets [probing depth (PD)≥6 mm] (17.9% vs. 41.9%, χ²=4.87, P=0.027), fewer number of PD≥4 mm (6.48±6.70 vs. 11.03±8.91, t=-2.44, P=0.017), lower plaque index (1.42±0.56 vs. 1.68±0.57, t=-1.91, P=0.059) and gingival index (1.68±0.29 vs. 1.96±0.30, t=-3.93, P<0.001) were in the control group than in the MCI group. However, there were no significant differences between the two groups in the levels of serum inflammatory factors, such as hs-CRP, IL-1β, IL-6 and TNF-α (P>0.05). Conclusions: It appears a strong correlation between moderate to severe periodontitis and the incidence of MCI in middle-aged and elderly people. Moreover, deep and increased number of periodontal pockets, poor oral hygiene, and severe gingival inflammation can be potentially associated risk factors for MCI.

Magnetic Resonance Imaging of Transplanted Porcine Neonatal Pancreatic Cell Clusters Labeled with Exendin-4-Conjugated Manganese Magnetism-Engineered Iron Oxide Nanoparticles

Recently, we have shown that manganese magnetism-engineered iron oxide nanoparticles (MnMEIO NPs) conjugated with exendin-4 (Ex4) act as a contrast agent that directly trace implanted mouse islet β-cells by magnetic resonance imaging (MRI). Here we further advanced this technology to track implanted porcine neonatal pancreatic cell clusters (NPCCs) containing ducts, endocrine, and exocrine cells. NPCCs from one-day-old neonatal pigs were isolated, cultured for three days, and then incubated overnight with MnMEIO-Ex4 NPs. Binding of NPCCs and MnMEIO-Ex4 NPs was confirmed with Prussian blue staining in vitro prior to the transplantation of 2000 MnMEIO-Ex4 NP-labeled NPCCs beneath the left renal capsule of six nondiabetic nude mice. The 7.0 T MRI on recipients revealed persistent hypointense areas at implantation sites for up to 54 days. The MR signal intensity of the graft on left kidney reduced 62–88% compared to the mirror areas on the contralateral kidney. Histological studies showed colocalization of insulin/iron and SOX9/iron staining in NPCC grafts, indicating that MnMEIO-Ex4 NPs were taken up by mature β-cells and pancreatic progenitors. We conclude that MnMEIO-Ex4 NPs are excellent contrast agents for detecting and long-term monitoring implanted NPCCs by MRI.

Magnetic Resonance Imaging of Transplanted Porcine Neonatal Pancreatic Cell Clusters Labeled with Chitosan-Coated Superparamagnetic Iron Oxide Nanoparticles in Mice

Neonatal pancreatic cell clusters (NPCCs) are potential tissues for the treatment of diabetes. Different from adult cells, they continuously proliferate and differentiate after transplantation. In this study, we utilized magnetic resonance imaging (MRI) to detect and monitor implanted NPCCs. NPCCs were isolated from one-day-old neonatal pigs, cultured for three days, and then incubated overnight with the contrast agent chitosan-coated superparamagnetic iron oxide (CSPIO) nanoparticles. In vitro, Prussian blue staining and MR scans of CSPIO-labeled NPCCs were performed. In vivo, we transplanted 2000 CSPIO-labeled NPCCs under the kidney capsule of nondiabetic nude mice. Recipients were scanned with 7.0T MRI. Grafts were removed for histology with insulin and Prussian blue staining. After being incubated overnight with CSPIO, NPCCs showed positive iron staining and appeared as dark spots on MR scans. After transplantation of CSPIO-labeled NPCCs, persistent hypointense areas were observed at recipients’ implant sites for up to 54 days. Moreover, histology showed colocalization of the insulin and iron staining in 15-, 51- and 55-day NPCC grafts. Our results indicate that transplanted NPCCs survived and differentiated to β cells after transplantation, and that MRI is a useful tool for the detection and monitoring of CSPIO-labeled NPCC grafts.

A Method for the Prediction of Clinical Outcome Using Diffusion Magnetic Resonance Imaging: Application on Parkinson's Disease

Robust early prediction of clinical outcomes in Parkinson's disease (PD) is paramount for implementing appropriate management interventions. We propose a method that uses the baseline MRI, measuring diffusion parameters from multiple parcellated brain regions, to predict the 2-year clinical outcome in Parkinson's disease. Diffusion tensor imaging was obtained from 82 patients (males/females = 45/37, mean age: 60.9 ± 7.3 years, baseline and after 23.7 ± 0.7 months) using a 3T MR scanner, which was normalized and parcellated according to the Automated Anatomical Labelling template. All patients were diagnosed with probable Parkinson's disease by the National Institute of Neurological Disorders and Stroke criteria. Clinical outcome was graded using disease severity (Unified Parkinson's Disease Rating Scale and Modified Hoehn and Yahr staging), drug administration (levodopa equivalent daily dose), and quality of life (39-item PD Questionnaire). Selection and regularization of diffusion parameters, the mean diffusivity and fractional anisotropy, were performed using least absolute shrinkage and selection operator (LASSO) between baseline diffusion index and clinical outcome over 2 years. Identified features were entered into a stepwise multivariate regression model, followed by a leave-one-out/5-fold cross validation and additional blind validation using an independent dataset. The predicted Unified Parkinson's Disease Rating Scale for each individual was consistent with the observed values at blind validation (adjusted R² 0.76) by using 13 features, such as mean diffusivity in lingual, nodule lobule of cerebellum vermis and fractional anisotropy in rolandic operculum, and quadrangular lobule of cerebellum. We conclude that baseline diffusion MRI is potentially capable of predicting 2-year clinical outcomes in patients with Parkinson's disease on an individual basis.

Functional human brain connectivity during labor and its alteration under epidural analgesia

This study used functional magnetic resonance imaging to explore the neural networks of pain during labor and its relief. It was hypothesized that epidural analgesia would affect the neural activities and the underlying network connectivity. Analysis using dynamic causal modelling and functional connectivity was performed to investigate the spatial activity and network connection of labor pain with and without epidural analgesia. This Institutional Review Board approved study acquired Magnetic Resonance Imaging from 15 healthy women of spontaneous normal delivery (with/without epidural analgesia = 7/8, aged 29.6 ± 2.3 and 29.3 ± 4.8 years old respectively) using a 1.5 Tesla scanner. Numerical rating score of pain was evaluated by a research nurse in the beginning of the first stage of labor and approximately 30 min after imaging examination. Six regions of interested from the activated clusters and literature were selected for dynamic causal modelling, which included primary and secondary somatosensory cortex, middle frontal gyrus, anterior cingulate cortex, insula and lentiform. Functional connectivity was calculated from selected sensory and affective regions. All analyses were performed by using software of statistical parametric mapping version 8 and CONN functional connectivity toolbox. The result showed that the experience of labor pain can lead to activations within a distributed brain network. The pain relief from epidural analgesia can be accompanied with altered functional connectivity, which was most evident in the cingulo-frontal system. The present study, therefore, provides an overview of a pain-related neural network that occur during labor and upon epidural analgesia.

A longitudinal fixel-based analysis of white matter alterations in patients with Parkinson's disease

INTRODUCTION

Disruption to white matter pathways is an important contributor to the pathogenesis of Parkinson's disease. Fixel-based analysis has recently emerged as a useful fiber-specific tool for examining white matter structure. In this longitudinal study, we used Fixel-based analysis to investigate white matter changes occurring over time in patients with Parkinson's disease.

METHODS

Fifty patients with idiopathic Parkinson's disease (27 men and 23 women; mean age: 61.8 ± 6.1 years), were enrolled. Diffusion-weighted imaging and clinical examinations were performed at three different time points (baseline, first follow-up [after a mean of 24±2 months], and second follow-up [after a mean of 40 ± 3 months]). Additional 76 healthy control subjects (38 men and 38 women; mean age: 62.3 ± 5.5 years) were examined at baseline. The following fixel-based metrics were obtained: fiber density (FD), fiber bundle cross-section (FC), and a combined measure of both (FDC). Paired comparisons of metrics between three different time points were performed in patients. Linear regression was implemented between longitudinal changes of fixel-based metrics and the corresponding modifications in clinical parameters. A family-wise error corrected p < 0.05 was considered statistically significant.

RESULTS AND DISCUSSIONS

Early degeneration in the splenium of corpus callosum was identified as a typical alteration of Parkinson's disease over time. At follow-up, we observed significant FDC reductions compared with baseline in white matter, noticeably in corpus callosum; tapetum; cingulum, posterior thalamic radiation, corona radiata, and sagittal stratum. We also identified significant FC decreases that reflected damage to white matter structures involved in Parkinson's disease -related pathways. Fixel-based metrics were found to relate with a deterioration of 39-item Parkinson's Disease Questionnaire, Unified Parkinson's Disease Rating Scale and activity of daily living. A Parkinson's disease -facilitated aging effect was observed in terms of white matter disruption.

CONCLUSION

This study provides a thorough fixel-based profile of longitudinal white matter alterations occurring in patients with Parkinson's disease and new evidence of FC as an important role in white matter degeneration in this setting.

Acupuncture Effect and Mechanism for Treating Pain in Patients With Parkinson's Disease

Non-motor symptoms of Parkinson's disease (PD) have been receiving increasing attention. Approximately half of patients with PD have experience PD-related pain. We investigated the effect and mechanism of acupuncture in patients with PD who have pain. PD patients with pain were divided into acupuncture group and control group. Nine patients completed acupuncture treatment; seven patients who received only an analgesic agent underwent resting-state functional magnetic resonance imaging (rs-fMRI) twice. fMRI was performed to evaluate the functional connectivity of the brain regions. After treatment, a decrease in total scores on the King's Parkinson's Disease Pain Scale (KPPS) and Unified Parkinson's Disease Rating Scale was observed in the acupuncture group (-46.2 and -21.6%, respectively). In the acupuncture group, increased connectivity was observed in four connections, one in the left hemisphere between the middle temporal gyrus (MTG) and precentral gyrus, and three in the right hemisphere between the postcentral gyrus and precentral gyrus, supramarginal gyrus and precentral gyrus, and MTG and insular cortex. A significant correlation was noted between the changes in functional connectivity and KPPS. The involved connection was between the left middle frontal gyrus and the right precentral gyrus (R = -0.698, P = 0.037). Acupuncture could relieve pain in PD patients by modulating brain regions related to both sensory-discriminative and emotional aspects. The present study might increase the confidence of users that acupuncture is an effective and safe analgesic tool that can relieve PD-related pain.

P4648Retrograde flow in aortic isthmus in fetuses with congenital heart defects and computer flow dynamic modeling

Background and objectives

Retrograde flow (RF) in the aortic isthmus is frequently observed in fetuses in various hemodynamic states including congenital heart defects (CHD). This study sought to: 1) establish the association between this observation and variables of CHD by fetal echocardiography (FE); and 2) to computer flow dynamic (CFD) model to probe the causes and mechanisms underlying this observation.

Methods

A total of 256 (gestational age (GA) 26.3±9.8 weeks) fetuses with CHD and 168 (GA: 25.8±10.3weeks) with normal FE were examined from January, 2011 to May, 2016. The study group was divided into: 1) no RF, 2) end systolic RF, end diastolic RF, systolic RF, diastolic RF, and systolic and diastolic RF sub-groups (Figure upper). GA, cerebroplacental ratio (CPR) of pulsatility index (PI) in middle cerebral and umbilical arteries, cardiothoracic area ratio (CTR), left and right atrial dimensions (LA/RA), left and right ventricular dimensions (LV/RV), aortic and pulmonary artery dimensions (AO/PA), and aortic isthmus and ductal arch dimensions (AI/DA), velocity ratio of aorta and pulmonary artery (AO/PAv), aortic isthmus and ductal arch in systolic (AI/DAvs) and diastolic (AI/DAvd). Using principal component analysis (PCA), the component score coefficient matrix and optional variance percent (OVP) was calculated by PCA and the RF pattern was simulated by CFD (Figure lower).

Results

RF modeling by CFD was feasible (Figure B). Component analysis by PCA showed that four types of variables were associated with RF: 1) Structural variables contribute 23.7% OVP, including LV/RV, LA/ RA, AO/PA, and IS/DA; 2) Resistance variables 16.8% OVP, i.e. CPR; 3) Growth variables 12.2% OVP, i,e, GA and CTR; and 4) Velocity variables 10.9% OVP, i.e. AO/PAv, AI/DAvd.

Retrograde flow by fetal echo and CFD

Conclusions

Retrograde flow in the aortic isthmus is associated with structural, resistance, growth, and velocity variables in fetal circulation in various CHD and normal 3rd trimester pregnancies. Simulation and modeling by CFD is feasible and may be useful to understand the causes and mechanisms of retrograde flow and its utility in diagnosis and prognosis in CHD.

Acknowledgement/Funding

Research on prevention and control of reproductive health and major birth defects

Using Hematuria as Detection of Post-kidney Transplantation Upper Urinary Tract Urothelial Carcinoma Is Associated With Delayed Diagnosis of Cancer Occurrence

OBJECTIVES

Kidney transplantation (KT) is an important renal replacement therapy for end-stage renal disease (ESRD). The incidence of upper urinary tract urothelial carcinoma (UTUC) is relatively higher in Taiwan. According to our institutional database, early onset of post-KT UTUC is not uncommon. Early detection of post-KT UTUC is an important issue to improve oncologic outcome. Because painless hematuria is a common symptom for UTUC, this study analyzes whether using hematuria as post-KT UTUC screening delayed cancer diagnosis or not.

METHODS

From 2005 to 2012, 128 ESRD patients were found to have UTUCs. There were 28 patients who underwent KT and were regularly followed up at our institution. All the patients underwent standard nephroureterectomy.

RESULTS

In ESRD patients with UTUC, the post-KT group revealed significantly less gross hematuria and microscopic hematuria at presentation compared with the non-KT group (43% versus 76%, P = .001 and 64% versus 86%, P = .011). For those patients with gross hematuria, non-organ-confined UTUC occurred more in the post-KT group compared with the non-KT group (42% versus 12%, P = .009). For those patients with microscopic hematuria, non-organ-confined UTUC occurred more in the post-KT group compared with the non-KT group with borderline significance (33% versus 16%, P = .085).

CONCLUSIONS

According to our observation, using gross or microscopic hematuria as detection of post-KT UTUC is associated with delayed diagnosis of cancer occurrence. Closer upper urinary tract image study such as sonography may help earlier cancer screening.

Increased Water Diffusion in the Parcellated Cortical Regions from the Patients with Amnestic Mild Cognitive Impairment and Alzheimer's Disease

Background: The loss of cortical neuron environment integrity is the hallmark of neurodegeneration diseases such as Alzheimer's disease (AD) and amnestic mild cognitive impairment (aMCI). To reveal the microenvironment changes in cerebral cortex, the current study aimed to examine the changes of mean diffusivity (MD) in parcellated brain among AD, aMCI patients and normal controls (NC).

Methods: Diffusion tensor imaging data with the whole brain coverage were acquired from 28 AD (aged 69.4 ± 8.2 year old), 41 aMCI patients (aged 68.2 ± 6.4 year old) and 40 NC subjects (aged 65.7 ± 6.4 year old). Subsequently, the MD values were parcellated according to the standard automatic anatomic labeling (AAL) template. Only the 90 regions located in the cerebral cortex were used in the final analysis. The mean values of MD from each brain region were extracted and compared among the participant groups. The integrity of the white matter tracts and gray matter atrophy was analyzed using the track-based spatial statistics and voxel-based morphometry approaches, respectively.

Results: Significant differences of MD were noticed both in aMCI and AD patients, in terms of the affected regions and the amount of increase. The hippocampus, parahippocampal gyrus and cingulum were the most significantly affected regions in AD patients. From all the 90 cerebral cortex regions, significant increase of MD in the AD patients was found in 40 regions, compared to only one (fusiform gyrus on the right) in aMCI patients. In the disease affected regions, the MD from aMCI patients is in state between NC and AD patients.

Conclusions: Increased MD in the specific regions of the brain shows the feasibility of MD as an indicator of the early stage cortical degeneration in aMCI and AD patients.

[Study of coenzyme Q10 in the liver of preeclampsia pregnant rats]

OBJECTIVE

To investigate the protective effect of coenzyme Q10 (CoQ10) in the liver of preeclampsiapregnant rats and the potential etiology.

METHODS

Fifty pregnant SD rats were equally divided into the normal pregnant (NP) group (n=10) and the preeclampsia (PE) group (n=40) randomly. The PE rats (n=40) were equally divided into four groups randomly, distilled water (DW) group, CoQ10 group, CoQ10 combined magnesium(CM) group and magnesium (Mg) group were established by treating the preeclampsia rats on day 15 to 21 of gestation with different measures. As for all the 50 rats, systolic blood pressure (SBP) of rat tail was detected on day 10, 15 and 21 of gestation respectively, 24 hours proteinuria analysis were detected on day 10, 15 and 21 of gestation respectively, levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) in blood andsuperoxide dismutase (SOD), glutathione peroxidase (GSH-PX), malondialdehyde (MDA), caspase-3, Bcl-2 and Bax protein expression in liver tissue were detected by western blot assay on day 21 of gestation.

RESULTS

(1) SBP and 24 hours proteinuria analysis: there was no statistic difference among all the five groups on day 10 of gestation (P>0.05). Whereas, SBP and 24 hours proteinuria analysis were significantly higher in CoQ10 group, CoQ10 combined CM group, CM group and DW group than that in NP group on day 15, 21 of gestation (P<0.05). And SBP and 24 hours proteinuria analysis were significantly lower in CoQ10 group, CoQ10 combined CM group and CM group than that in DW group on day 21 of gestation (P<0.05). (2) Liver function: among CoQ10 group, CoQ10 combined CM group, CM group, DW group and NP group, serum levels of ALT were respectively (52±7) , (34±9) , (49±10) , (70±19) , (30±7) U/L; and serum levels of AST were respectively (169±25) , (84±11) , (159±20) , (281±26) and (78±18) U/L. ALT and AST serum levels were significantly higher in CoQ10 group, CM group and DW group than that in NP group (P<0.05). ALT and AST serum levels were significant lower in CoQ10 combined CM group than those in CoQ10 group, CM group and DW group, respectively (P<0.05). ALT and AST serum levels were significant lower in CoQ10 group and CM group than that in DW group, respectively (P<0.05). (3) SOD, GSH-PX, MDA, caspase-3, Bcl-2 and Bax expression in liver tissue of rats: SOD expression was significant higher in CoQ10 group, CoQ10 combined CM group than thoes in CM group, DW group and NP group (P<0.05) ; SOD expression was significant lower in CM group, DW grouo than thoes in NP group (P<0.05) ; and SOD expression was significant higher in CM group than that in DW group (P<0.05) . Compared with CoQ10 group, CoQ10 combined CM group, CW group and DW group respectively, the GSH-PX and Bcl-2 protein expressions were significant higher in NP group (P<0.05) , while MDA, caspase-3 and Bax protein expressions were significant lower in NP group (P<0.05) ; compared with CoQ10 group, CoQ10 combined CM group and CW group respectively, the GSH-PX and Bcl-2 protein expressions were significant lower in DW group (P<0.05) , while MDA, caspase-3 and Bax protein expressions were significant higher in DW group (P<0.05) .

CONCLUSIONS

Oxidative stress and apoptosis levles were upregulated in PE pregnant liver tissues. CoQ10 could effectively protect the liver by improving the liver functions and decreasing the apoptosis of liver cells in PE pregnant rats, and markedly decrease the oxidative stress and apoptosis in the livers. The protective roles of CoQ10 in liver might through its function of anti-oxidative stress and inhibiting cell apoptosis by regulating the balance of Bcl-2/Bax.

Association of Epstein-Barr virus infection with systemic lupus erythematosus in Taiwan

An association between Epstein-Barr virus (EBV) infection and systemic lupus erythematosus (SLE) has been suggested from previous serologic evidence. Since most adults in Taiwan are EBV-infected, seroepidemiologic studies based on standard assays for EBV are unlikely to dissociate SLE patients and control groups. We reexamine this question by using novel methodologies in which IgA anti-EBV-coded nuclear antigens-1 (EBNA-1) and IgG anti-EBV DNase antibodies were analysed by ELISA, and EBV viral loads were detected by real-time quantitative PCR for 93 adult SLE patients and 370 age-, sex- and living place-matched healthy controls in Taiwan. The specificities of antibodies for extractible nuclear antigens were determined by Western blot. Our results show that IgA anti-EBV EBNA1 antibodies were detectable in 31.2% SLE patients but only in 4.1% of controls (odds ratio [OR] = 10.72, 95% confidence interval [CI] = 5.19–22.35; P < 10-7), IgG anti-EBV DNase antibodies were detected in 53.8% SLE patients but only in 12.2% controls (OR = 8.40, 95% CI = 4.87–14.51; P < 10-7). EBV DNA was amplifiable from the sera of 41.9% SLE patients but from only 3.24% controls ( P < 0.05). A significant association of IgG anti-EBV DNase antibodies with anti-Sm/RNP antibodies was observed ( P < 0.005). The higher seroreactivity and higher copy numbers of EBV genome indicated association of EBV infection with SLE in Taiwan.

Efficacy of percutaneous radiofrequency ablation for the treatment of hepatocellular carcinoma

In this study, we sought to evaluate the efficacy of transcatheter arterial chemoembolization (TACE) plus radiofrequency ablation (RFA; experimental group) versus RFA treatment (control group) in patients receiving palliative treatment for hepatocellular carcinoma. To summarize the available evidence, we used the Review Manager 5.1 software to perform a meta-analysis of English-language articles published in public databases prior to 2014. Based on 6 studies that met the inclusion criteria, a total of 531 (experimental group, 272; control group, 259) patients with hepatocellular carcinoma were included in the meta-analysis. The meta-analysis demonstrated that the experimental group had a higher 3-year survival rate [risk ratios (RRs) = 1.41; 95% confidence interval (CI) = 1.03-1.94; P < 0.05] and a higher 2-year survival rate (RR = 1.11; 95%CI = 1.01-1.23; P < 0.05) than the control group. In the overall meta-analysis, the overall RRs were 2.02 (95%CI = 1.40-2.91; P < 0.05) and 1.63 (95%CI = 1.06-2.51; P < 0.05) for 3- and 5-year recurrence-free survival, respectively. Furthermore, the overall meta-analysis showed an overall RR of 0.75 (95%CI = 0.60-0.93; P < 0.05) for the incidence of tumor progression and an overall RR of 1.19 (95%CI = 0.33-4.33; P > 0.05) for the major complication rate. In a sensitivity analysis, the above mentioned meta-analytic estimates were unchanged by the removal of 1 study at a time. The meta-analysis suggested that the experimental group had a higher survival rate, a higher recurrence-free survival rate, and a lower incidence of tumor progression than the corresponding control group.

Quantum-mechanical approach to predissociation of water dimers in the vibrational adiabatic representation: Importance of channel interactions

The results of application of the quantum-mechanical adiabatic theory to vibrational predissociation (VPD) of water dimers, (H2O)2 and (D2O)2, are presented. We consider the VPD processes including the totally symmetric OH mode of the dimer and the bending mode of the fragment. The VPD in the adiabatic representation is induced by breakdown of the vibrational adiabatic approximation, and two types of nonadiabatic coupling matrix elements are involved: one provides the VPD induced by the low-frequency dissociation mode and the other provides the VPD through channel interactions induced by the low-frequency modes. The VPD rate constants were calculated using the Fermi golden rule expression. A closed form for the nonadiabatic transition matrix element between the discrete and continuum states was derived in the Morse potential model. All of the parameters used were obtained from the potential surfaces of the water dimers, which were calculated by the density functional theory procedures. The VPD rate constants for the two processes were calculated in the non-Condon scheme beyond the so-called Condon approximation. The channel interactions in and between the initial and final states were taken into account, and those are found to increase the VPD rates by 3(1) orders of magnitude for the VPD processes in (H2O)2 ((D2O)2). The fraction of the bending-excited donor fragments is larger than that of the bending-excited acceptor fragments. The results obtained by quantum-mechanical approach are compared with both experimental and quasi-classical trajectory calculation results.

Role of the CKIP1 gene in proliferation and apoptosis of the human lung cancer cell line H1299

Casein kinase 2 interacting protein 1 (CKIP1) is a specific interacting protein of the casein kinase 2 (CK2) α subunit, and, by binding CK2 and other proteins, functions as an adaptor to regulate a series of cellular functions. Previous studies suggested that CKIP1 might play an important role in regulating oncogenic activities. However, few studies examining the function of CKIP1 in cancer cells have been performed. The present study aimed to investigate the role of CKIP1 in lung cancer. CKIP1 mRNA expression was detected in 5 human lung cancer cell lines (H-125, H1299, LTEP-A-2, SPC-A-1, and NCL-H446) by semi-quantitative RT-PCR, and in 10 noncancerous lung tissues and 30 non-small lung cancer tissues by real-time quantitative PCR. A lentivirus-mediated small interfering RNA (siRNA) was used to knock down CKIP1 expression in the H1299 cell line. To elucidate the impact of CKIP1 downregulation on H1299 cells, cell proliferation, DNA synthesis, and cell cycle distribution and apoptosis were measured by high content screening assay, BrdU incorporation, and flow cytometric analyses, respectively. CKIP1 mRNA was highly expressed both in H1299 cells and lung cancer tissues. We found that downregulation of CKIP1 resulted in suppression of proliferation and colony-forming ability of H1299 cells, and led to S phase cell cycle arrest and G2 phase promotion, as well as a significant enhancement of H1299 cell apoptosis. Our study indicated that high expression levels of CKIP1 were associated with the development of lung cancer, and that CKIP1 knockdown may block tumor cell growth mainly by promoting cell apoptosis.

First Report of Corn Kernel Brown Spot Disease Caused by Mucor irregularis in China

In October 2012, a brown spot disease was found on corn kernels during a field survey in Nanyang city (33°01' N, 112°29' E), China. The incidences of affected ears and kernels were 2 to 10% (n = 600) and 0.08 to 0.4% (n = 25,000), respectively. Symptoms first appeared as circular or irregular brown spots on the endosperm. These spots subsequently enlarged or coalesced, resulting in the formation of a large light-brown or light-yellow irregular speckle commonly surrounded by a dark-brown edge. Pure fungal cultures with similar morphological characteristics were obtained from surface-disinfected symptomatic kernels using a conventional method for isolation of culturable microbes. The isolated fungal cultures were purified by single-spore isolation (3). A representative isolate F1 was randomly selected, used for pathogenicity tests, and identified using morphological and molecular methods. Colonies on PDA were circular with abundant villiform aerial mycelia. The color of colonies was white-gray at first and turned to light yellow or became ochraceous after 3 days of incubation at 28°C. Hyphae were hyaline and less septate, with rectangular branches. Sporangiophores were erect and unbranched or branched, with globose sporangia formed on their tips. Sporangiospores were elliptical to round, 3.6 to 7.3 × 1.6 to 3.7 μm (n = 100) in size. Two gene regions were amplified for multilocus sequence typing. The D1/D2 region of the nuclear large subunit ribosomal RNA gene (nucLSU) was amplified with primers NL1 and NL4 and the rDNA internal transcribed spacer (ITS) with primers ITS1 and ITS4. PCR products were purified using an Axygen nucleic acid purification kit for sequencing. Both rDNA D1/D2 and rDNA-ITS sequences were submitted to GenBank with accession numbers KM093834 and KM203872, respectively. The isolate F1 showed 98% identity with two isolates of Mucor irregularis (KC524427 and KC461926) in rDNA-ITS sequences and 99% identity with multiple isolates (JX976221, JX976203, and JX976219) of M. irregularis in rDNA D1/D2 sequences. Pathogenicity tests of isolate F1 were conducted based on Koch's postulates. Thirty kernels of fresh ears (milk stage) were pricked by sterilized toothpicks and separately inoculated with a sporangiospore suspension (1 × 10⁶ spores/ml) and 5-day-old mycelial plugs (5 × 5 mm) of isolate F1. Kernels on ears that were inoculated with sterilized water and pure PDA plugs were separately used as controls. After 7 days of incubation, brown spot symptoms developed on the F1-inoculated kernels, which were similar to those observed on the naturally infected ears from the field samples. The control ears remained symptomless during the inoculation tests. Fungal cultures showing the same morphological characteristics as those of isolate F1 were consistently recovered from the diseased cobs inoculated by isolate F1, indicating that M. irregularis was responsible for corn kernel brown spot disease. M. irregularis was reported as a pathogen causing human skin diseases in China (5), America (1), and India (2) and as a phytopathogen causing fruit rot on durian (4). This is the first report of M. irregularis causing corn kernel brown spot disease in China. References: (1) M. M. Abuali et al. J. Clin. Microbiol. 47:4176, 2009. (2) B. M. Hemashettar et al. J. Clin. Microbiol. 49:2372, 2011. (3) S. L. Huang and K. Kohmoto. Bull. Fac. Agric., Tottori Univ. 44:1, 1991. (4) W. F. Wang et al. Plant Quarant. l23:60, 2009. (5) Y. Zhao et al. Mycopathologia 168:243, 2009.

Study on a negative hydrogen ion source with hot cathode arc discharge

A negative hydrogen (H(-)) ion source with hot cathode arc discharge was designed and fabricated as a primary injector for a 10 MeV PET cyclotron at IMP. 1 mA dc H(-) beam with ɛ N, RMS = 0.08 π mm mrad was extracted at 25 kV. Halbach hexapole was adopted to confine the plasma. The state of arc discharge, the parameters including filament current, arc current, gas pressure, plasma electrode bias, and the ratio of I(e(-))/I(H(-)) were experimentally studied. The discussion on the result, and opinions to improve the source were given.

First Report of Pepper Fruit Rot Caused by Fusarium concentricum in China

Pepper (Capsicum annuum L.) is an important vegetable crop worldwide. Some Fusarium species can cause pepper fruit rot, leading to significant yield losses of pepper production and, for some Fusarium species, potential risk of mycotoxin contamination. A total of 106 diseased pepper fruit samples were collected from various pepper cultivars from seven provinces (Gansu, Hainan, Heilongjiang, Hunan, Shandong, Shanghai, and Zhejiang) in China during the 2012 growing season, where pepper production occurs on approximately 25,000 ha. Pepper fruit rot symptom incidence ranged from 5 to 20% in individual fields. Symptomatic fruit tissue was surface-sterilized in 0.1% HgCl₂ for 1 min, dipped in 70% ethanol for 30 s, then rinsed in sterilized distilled water three times, dried, and plated in 90 mm diameter petri dishes containing potato dextrose agar (PDA). After incubation for 5 days at 28°C in the dark, putative Fusarium colonies were purified by single-sporing. Forty-three Fusarium strains were isolated and identified to species as described previously (1,2). Morphological characteristics of one strain were identical to those of F. concentricum. Aerial mycelium was reddish-white with an average growth rate of 4.2 to 4.3 mm/day at 25°C in the dark on PDA. Pigments in the agar were formed in alternating red and orange concentric rings. Microconidia were 0- to 1-septate, mostly 0-septate, and oval, obovoid to allantoid. Macroconidia were relatively slender with no significant curvature, 3- to 5-septate, with a beaked apical cell and a foot-shaped basal cell. To confirm the species identity, the partial TEF gene sequence (646 bp) was amplified and sequenced (GenBank Accession No. KC816735). A BLASTn search with TEF gene sequences in NCBI and the Fusarium ID databases revealed 99.7 and 100% sequence identity, respectively, to known TEF sequences of F. concentricum. Thus, both morphological and molecular criteria supported identification of the strain as F. concentricum. This strain was deposited as Accession MUCL 54697 (http://bccm.belspo.be/about/mucl.php). Pathogenicity of the strain was confirmed by inoculating 10 wounded, mature pepper fruits that had been harvested 70 days after planting the cultivar Zhongjiao-5 with a conidial suspension (1 × 10⁶ spores/ml), as described previously (3). A control treatment consisted of inoculating 10 pepper fruits of the same cultivar with sterilized distilled water. The fruit were incubated at 25°C in a moist chamber, and the experiment was repeated independently in triplicate. Initially, green to dark brown lesions were observed on the outer surface of inoculated fruit. Typical soft-rot symptoms and lesions were observed on the inner wall when the fruit were cut open 10 days post-inoculation. Some infected seeds in the fruits were grayish-black and covered by mycelium, similar to the original fruit symptoms observed at the sampling sites. The control fruit remained healthy after 10 days of incubation. The same fungus was isolated from the inoculated infected fruit using the method described above, but no fungal growth was observed from the control fruit. To our knowledge, this is the first report of F. concentricum causing a pepper fruit rot. References: (1) J. F. Leslie and B. A. Summerell. The Fusarium Laboratory Manual. Blackwell Publishing, Ames, IA, 2006. (2) K. O'Donnell et al. Proc. Nat. Acad. Sci. USA 95:2044, 1998. (3) Y. Yang et al. 2011. Int. J. Food Microbiol. 151:150, 2011.

Association between clinical complete response and pathological complete response after preoperative chemoradiation in patients with gastroesophageal cancer: analysis in a large cohort

BACKGROUND

Chemoradiation followed by surgery is the preferred treatment of localized gastroesophageal cancer (GEC). Surgery causes considerable life-altering consequences and achievement of clinical complete response (clinCR; defined as postchemoradiation [but presurgery] endoscopic biopsy negative for cancer and positron emission tomographic (PET) scan showing physiologic uptake) is an enticement to avoid/delay surgery. We examined the association between clinCR and pathologic complete response (pathCR).

PATIENTS AND METHODS

Two hundred eighty-four patients with GEC underwent chemoradiation and esophagectomy. The chi-square test, Fisher exact test, t-test, Kaplan-Meier method, and log-rank test were used.

RESULTS

Of 284 patients, 218 (77%) achieved clinCR. However, only 67 (31%) of the 218 achieved pathCR. The sensitivity of clinCR for pathCR was 97.1% (67/69), but the specificity was low (29.8%; 64/215). Of the 66 patients who had less than a clinCR, only 2 (3%) had a pathCR. Thus, the rate of pathCR was significantly different in patients with clinCR than in those with less than a clinCR (P < 0.001).

CONCLUSIONS

clinCR is not highly associated with pathCR; the specificity of clinCR for pathCR is too low to be used for clinical decision making on delaying/avoiding surgery. Surgery-eligible GEC patients should be encouraged to undergo surgery following chemoradiation despite achieving a clinCR.

Face recognition/detection by probabilistic decision-based neural network

This paper proposes a face recognition system, based on probabilistic decision-based neural networks (PDBNN). With technological advance on microelectronic and vision system, high performance automatic techniques on biometric recognition are now becoming economically feasible. Among all the biometric identification methods, face recognition has attracted much attention in recent years because it has potential to be most nonintrusive and user-friendly. The PDBNN face recognition system consists of three modules: First, a face detector finds the location of a human face in an image. Then an eye localizer determines the positions of both eyes in order to generate meaningful feature vectors. The facial region proposed contains eyebrows, eyes, and nose, but excluding mouth (eye-glasses will be allowed). Lastly, the third module is a face recognizer. The PDBNN can be effectively applied to all the three modules. It adopts a hierarchical network structures with nonlinear basis functions and a competitive credit-assignment scheme. The paper demonstrates a successful application of PDBNN to face recognition applications on two public (FERET and ORL) and one in-house (SCR) databases. Regarding the performance, experimental results on three different databases such as recognition accuracies as well as false rejection and false acceptance rates are elaborated. As to the processing speed, the whole recognition process (including PDBNN processing for eye localization, feature extraction, and classification) consumes approximately one second on Sparc10, without using hardware accelerator or co-processor.

Clinical parameters model for predicting pathologic complete response following preoperative chemoradiation in patients with esophageal cancer

BACKGROUND

Approximately 25% of patients with esophageal cancer (EC) who undergo preoperative chemoradiation, achieve a pathologic complete response (pathCR). We hypothesized that a model based on clinical parameters could predict pathCR with a high (≥60%) probability.

PATIENTS AND METHODS

We analyzed 322 patients with EC who underwent preoperative chemoradiation. All the patients had baseline and postchemoradiation positron emission tomography (PET) and pre- and postchemoradiation endoscopic biopsy. Logistic regression models were used for analysis, and cross-validation via the bootstrap method was carried out to test the model.

RESULTS

The 70 (21.7%) patients who achieved a pathCR lived longer (median overall survival [OS], 79.76 months) than the 252 patients who did not achieve a pathCR (median OS, 39.73 months; OS, P = 0.004; disease-free survival, P = 0.003). In a logistic regression analysis, the following parameters contributed to the prediction model: postchemoradiation PET, postchemoradiation biopsy, sex, histologic tumor grade, and baseline (EUS)T stage. The area under the receiver-operating characteristic curve was 0.72 (95% confidence interval [CI] 0.662-0.787); after the bootstrap validation with 200 repetitions, the bias-corrected AU-ROC was 0.70 (95% CI 0.643-0.728).

CONCLUSION

Our data suggest that the logistic regression model can predict pathCR with a high probability. This clinical model could complement others (biomarkers) to predict pathCR.

Adiabatically slow and adiabatically fast driven ratchets

We revisit two known models of deterministically driven ratchets, which exhibit high energetic efficiency, with the goal to uncover similarities and differences in the principles of their operation. Both the models rely on adiabaticity of the potential change process, however, the adiabaticity that we deal with in the two cases is of different types, slow and fast. It is shown that in the former (latter) case the drift velocity is an even (odd) functional of the potential, with the notable consequence that for the adiabatically slow driven ratchet the necessary symmetry breaking occurs only due to time-dependent parametric perturbations, while the spatial asymmetry of the potential is a mandatory condition for the adiabatically fast driven ratchet to operate. To treat energetic characteristics, the models are restated in terms of traveling potential ratchets. With such an approach, we find that in these cases (i) the conditions of high energetic efficiency to be reached are similar, and (ii) the symmetry properties of the kinetic coefficients are different. Based on our results, a strategy for designing efficient Brownian motors is suggested.

Development of DRAGON electron cyclotron resonance ion source at Institute of Modern Physics

A new room temperature electron cyclotron resonance (ECR) ion source, DRAGON, is under construction at IMP. DRAGON is designed to operate at microwaves of frequencies of 14.5-18 GHz. Its axial solenoid coils are cooled with evaporative medium to provide an axial magnetic mirror field of 2.5 T at the injection and 1.4 T at the extraction, respectively. In comparison to other conventional room temperature ECR ion sources, DRAGON has so far the largest bore plasma chamber of inner diameter of 126 mm with maximum radial fields of 1.4-1.5 T produced by a non-Halbach permanent sextupole magnet.

Status of the laser ion source at IMP

A laser (Nd:YAG laser, 3 J, 1064 nm, 8-10 ns) ion source has been built and under development at IMP to provide pulsed high-charge-state heavy ion beams to a radio frequency quadrupole (RFQ) for upgrading the IMP accelerators with a new low-energy beam injector. The laser ion source currently operates in a direct plasma injection scheme to inject the high charge state ions produced from a solid target into the RFQ. The maximum power density on the target was about 8.4 × 10(12) W∕cm(2). The preliminary experimental results will be presented and discussed in this paper.

A 2.45 GHz electron cyclotron resonance proton ion source and a dual-lens low energy beam transport

The structure and preliminary commissioning results of a new 2.45 GHz ECR proton ion source and a dual-lens low energy beam transport (LEBT) system are presented in this paper. The main magnetic field of the ion source is provided by a set of permanent magnets with two small electro-solenoid magnets at the injection and the extraction to fine tune the magnetic field for better microwave coupling. A 50 keV pulsed proton beam extracted by a three-electrode mechanism passes through the LEBT system of length of 1183 mm. This LEBT consists of a diagnosis chamber, two Glaser lenses, two steering magnets, and a final beam defining cone. A set of inner permanent magnetic rings is embedded in each of the two Glaser lenses to produce a flatter axial-field to reduce the lens aberrations.

Study of ion beam transport from the SECRAL electron cyclotron resonance ion source at the Institute of Modern Physics

Ion beam transport from the Superconducting Electron Cyclotron Resonance ion source with Advanced design in Lanzhou (SECRAL) electron cyclotron resonance ion source was studied at the Institute of Modern Physics during 2010. Particle-in-cell simulations and experimental results have shown that both space charge and magnetic aberrations lead to a larger beam envelope and emittance growth. In the existing SECRAL extraction beam line, it has been shown that raising the solenoid lens magnetic field reduces aberrations in the subsequent dipole and results in lower emittance. Detailed beam emittance measurements are presented in this paper.

Characterization of carbapenem-nonsusceptible Klebsiella pneumoniae bloodstream isolates at a Taiwanese hospital: clinical impacts of lowered breakpoints for carbapenems

This study was conducted in order to characterize carbapenem-nonsusceptible Klebsiella pneumoniae isolates and to evaluate the impacts of recently lowered interpretative breakpoints for carbapenems for Enterobacteriaceae. Among 152 K. pneumoniae bloodstream isolates suspected as AmpC or extended-spectrum β-lactamase (ESBL) producers, 58 (38.2%) isolates were currently interpreted as nonsusceptible to ertapenem, imipenem, or meropenem, and 42 (72.4%) of them were categorized as carbapenem-susceptible by the previous criteria. The high revision rate was associated with the predominance (79.3%) of DHA-1 among the carbapenem-nonsusceptible isolates due to both polyclonal and clonal spread. ESBLs were common (~57%) in both ertapenem-susceptible and -nonsusceptible isolates; however, 84.8% of the carbapenem-nonsusceptible isolates were also AmpC producers. The IMP-8 metallo-β-lactamase was detected in three isolates. Polyacrylamide gel electrophoresis suggested decreased OmpK35 expression in all but one ertapenem-nonsusceptible isolate, and genetic disruptions of ompK35 and ompK36 were detected in 30 and six ertapenem-nonsusceptible isolates, respectively. A comparison between patients infected by AmpC- or ESBL-producing ertapenem-susceptible (n=62) isolates and those with isolates revised as ertapenem-nonsusceptible (n=41) revealed more cases of malignancies (36.6% versus 14.5%; p=0.01) and higher Charlson score (p=0.033) among the patients with ertapenem-nonsusceptible isolates; however, the acquisition of an isolate revised as carbapenem-nonsusceptible was not identified as an independent mortality risk factor.

Patients with high body mass index tend to have lower stage of esophageal carcinoma at diagnosis

High body mass index (H-BMI; ≥25 kg/m(2) ) is common in US adults. In a small cohort of esophageal cancer (EC) patients treated with surgery, H-BMI and diagnosis of early stage EC appeared associated. We evaluated a much larger cohort of EC patients. From a prospectively maintained database, we analyzed 925 EC patients who had surgery with or without adjunctive therapy. Various statistical methods were used. Among 925 patients, 69% had H-BMI, and 31% had normal body mass index (<25 kg/m(2) ; N-BMI). H-BMI was associated with men (P<0.001), Caucasians (P=0.064; trend), lower esophageal localization (P<0.001), adenocarcinoma histology (P<0.001), low baseline cT-stage (P=0.003), low baseline overall clinical stage (P=0.003), coronary artery disease (P=0.036), and diabetes (P<0.001). N-BMI was associated with weight loss (P<0.001), alcohol abuse (P=0.056; trend), ever/current smoking (P=0.014), and baseline cN+ (P=0.018). H-BMI patients with cT1 tumors (n=110) had significantly higher rates of gastresophageal reflux disease symptoms (P<0.001), gastresophageal reflux disease history (P<0.001), and Barrett's esophagus history (P<0.001) compared with H-BMI patients with cT2 tumors (n=114). Median survival of N-BMI patients was 36.66 months compared with 53.20 months for H-BMI patients (P=0.005). In multivariate analysis, older age (P<0.001), squamous histology (P=0.002), smoking (P=0.040), weight loss (P=0.002), high baseline stage (P<0.001), high number of ypN+ (P=0.005), high surgical stage (P<0.001), and American Society of Anesthesia scores, three out of four (P<0.001) were independent prognosticators for poor overall survival. We were able to perform propensity-based analysis of surgical complications between H-BMI and N-BMI patients. A comparison of fully matched 376 patients (188 with H-BMI and 188 with N-BMI) found no significant differences in the rate of complications between the two groups. This larger data set confirms that a fraction of H-BMI patients with antecedent history is diagnosed with early baseline EC. Upon validation of our data in an independent cohort, refinements in surveillance of symptomatic H-BMI patients are warranted and could be implemented. Our data also suggest that H-BMI patients do not experience higher rate of surgical complications compared with N-BMI patients.

Two-state Brownian motor driven by synchronously fluctuating unbiased forces

As a model of the Brownian motor, we consider a particle moving unidirectionally under the action of two synchronously fluctuating unbiased forces, transverse and longitudinal with respect to the particle track. The former force induces track-normal transitions of the particle between the attached and detached states (with and without a periodic potential, respectively), whereas the latter drives track-parallel motion in either state. Analytical expressions of the current and efficiency are derived for different regimes, with due account of the delayed response of the system to force fluctuations. For a sawtooth potential in the attached state, we reveal several motion regimes affording the maximum current or the maximum efficiency. A special emphasis is placed on the possibility of current reversal. As shown, the interplay between two phase-shifted harmonically varied forces as well as inherent and externally induced asymmetry can lead to the emergence of multiple current reversals, thus enabling the flexible controllability of the motion direction.

Infections caused by Gordonia species at a medical centre in Taiwan, 1997 to 2008

The inability of conventional identification systems to accurately identify Gordonia spp. often results in the misdiagnosis of infections by these rare pathogens, which require genomic sequencing for precise identification. In the present study, we describe nine cases of the various types of infection caused by Gordonia spp. From 1997 to 2008, 66 isolates (from 30 patients) initially identified as Rhodoccus spp. by conventional biochemical methods, by the Bacteriology Laboratory of National Taiwan University Hospital, were retrospectively analysed to assess the accuracy of species identification. Fifteen of these isolates (from nine patients) were later found to be Gordonia spp. by two molecular methods: PCR-restriction fragment length polymorphism for heat shock protein gene (hsp65) and the 16S rRNA gene sequencing analysis. Gordonia sputi (n = 8) was the most common species, followed by Gordonia terrae (n = 7). Most of the isolates were isolated from blood (n = 11), followed by soft tissue (n = 2) and eye (n = 2). Five patients presented with bacteraemia and two of these had catheter-related bloodstream infection. Two patients had soft tissue infections and another two patients had infective keratitis and conjunctivitis. The random amplified polymorphic DNA patterns for isolates from different patients were different, indicating that they were genetically unrelated. Accurate identification with molecular methods is required if the role of Gordonia spp. in causing infection is to be recognized.

A master equation approach to the dynamics of zero electron kinetic energy (ZEKE) states and ZEKE spectroscopy

We have theoretically studied important dynamic processes involved in zero electron kinetic energy (ZEKE) spectroscopy using the density matrix method with the inverse Born-Oppenheimer approximation basis sets. In ZEKE spectroscopy, the ZEKE Rydberg states are populated by laser excitation (either a one- or two-photon process), which is followed by autoionizations and l-mixing due to a stray field. The discrimination field is then applied to ionize loosely bound electrons in the ZEKE states. This is followed by using the extraction field to extract electrons from the ZEKE levels which have a strength comparable to that of the extraction field. These extracted electrons are measured for the relative intensities of the ion states under investigation. The spectral positions are determined by the applied laser wavelength and modified by the extraction electric field. In this paper, all of these processes are conducted within the context of the density matrix method. The density matrix method can provide not only the dynamics of system's population and coherence (or phase) but also the rate constants of the processes involved in the ZEKE spectroscopy. Numerical examples are given to demonstrate the theoretical treatments.

Clinical significance of nontuberculous mycobacteria isolates in elderly Taiwanese patients

The aim of this study was to investigate the clinical significance of nontuberculous mycobacteria (NTM) isolates in elderly Taiwanese patients. From 2004 through 2008, patients >65 years old with NTM isolation were identified. The definitions of NTM disease followed the American Thoracic Society and Infectious Disease Society of America (ATS/IDSA) criteria. Among the 3,175 NTM isolates, Mycobacterium avium complex (MAC; n = 1,118, 35.2%) was the most prevalent species, followed by M. abscessus (n = 545, 17.2%). Among the 1,633 elderly patients with NTM isolates, the most prevalent NTM species were MAC (n = 592, 36.3%) and M. fortuitum complex (n = 311, 19.0%). NTM colonization was found in 1,339 (80.4%) patients and only 326 (19.6%) patients had NTM diseases. During the study period, the annual incidence rates (per 100,000 inpatients and outpatients) of NTM colonization and disease both increased significantly (p < 0.0001) from 10.5 to 15.8 and from 2.1 to 4.3, respectively. Isolated pulmonary NTM infections compromised 294 (90.2%) of the 326 elderly cases of NTM disease. In conclusion, this study found an increasing trend in the incidence of both NTM isolates and NTM diseases among elderly Taiwanese patients. MAC and M. abscessus were the most frequent species causing various types of NTM disease.

A theoretical study of resonance Raman scattering from molecules: High pressure effect

The main purpose of this paper has been to study the high pressure effect on the resonance Raman scattering (RRS) of molecules in a dense medium. In deriving the RRS cross section under high pressure, a different approach from that presented in the previous papers has been used, and the resulting expression for the RRS cross section can be used to treat both pressure and temperature effects.

Mechanisms of triboluminescence

The purpose of this paper has been to develop the theoretical treatment of the triboexcitation mechanisms due to the electric field effect and the pressure effect and to show how to analyze the triboluminescent spectra to determine the external factors that affect or induce the triboluminescence.

Quantum statistical theory of optical phenomena

The purpose of this paper is to develop a density matrix formulation for optical phenomena that can be applied to both steady and transient states and to both resonance and off-resonance regions. To demonstrate the application, this theory has been applied to the steady-state one-photon and two-photon processes. We have found that, in the resonance region, the conventional equation used is incomplete; other terms that are comparable in importance have been ignored.

Solution of the time-dependent schrödinger equation by the laplace transform method

The time-dependent Schrödinger equation for two quite general types of perturbation has been solved by introducing the Laplace transforms to eliminate the time variable. The resulting time-independent differential equation can then be solved by the perturbation method, the variation method, the variation-perturbation method, and other methods.

A general treatment of relaxation phenomena

The singular perturbation method has been applied to solve the quantum mechanical Liouville equation for the relaxation phenomenon of the system in thermal contact with a heat bath. The master equation derived gives the proper expressions for both diagonal and off-diagonal elements of the density matrix and is capable of describing the time-dependent behavior of the system in the time range comparable with the reciprocal of the damping constants and the time range t --> infinity compared with the reciprocal of the damping constants.