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Flavin containing monooxygenase 3 (FMO3) is a member of the flavin monooxygenase family, which can oxidize the precursor Trimethylamine (TMA) provided from food to produce Trimethylamine N-oxide (TMAO). The autosomal recessive inherited disease caused by partial functional loss of Fmo3 gene, which leads to excessive excretion of TMA in body fluids and emits fishy odor, is called Fish Odor Syndrome or Trimethylaminuria. This disease has been documented for 3,000 years ago and was first reported in the case report in 1970. FMO3 mainly exists in the liver and can participate in the TMA-TMAO metabolic balance in intestinal microorganisms, liver, and kidneys, closely related to insulin resistance, diabetes, cholesterol metabolism, and cardiovascular disease. Due to its wide range of catalytic substrates and low susceptibility to metabolite accumulation, its role in drug metabolism, new drug development, and discovery of new drug targets are increasingly valued. This review will summarize the research progress on the metabolic process and localization of FMO3, congenital genetic defects, metabolic diseases, and its related possible mechanisms. [ABSTRACT FROM AUTHOR]

OBJECTIVES To evaluate the effectiveness of a large-scale, web-based, in-service hypertension management training project among lay health workers (LHWs) at primary care health (PHC) settings in China, and to examine the factors contributing to the variations of effectiveness. METHODS We used data from a web-based national hypertension management training project implemented in 2018, it was designed to facilitate LHWs to learn, understand, and apply the relevant knowledge and skills in hypertension management through providing training courses by use of the web-based platform with unified standards. All LHWs were required to participate in the exams before and after training to acquire scores for the use of evaluating their performance of hypertension management knowledge. We first used descriptive analysis to present the variations of effectiveness in hypertension management knowledge among LHWs by important subgroups. Afterwards, we used multilevel logistic regression to examine the individual and regional factors contributing to the variations and quantify the magnitude of how these factors affected training effectiveness. RESULTS There were 1,208,610 LHWs who completed training and were certificated. Nationally, the scores of LHWs increased significantly from 62.87 ± 21.14 out of 100 in the pre-test to 88.30 ± 11.31 in the post-test by 25.43 (95% confidence interval [CI]: 25.40-25.47). Training contents involved in antihypertensive medication showed the lowest score (54.36) in the pre-test and soared the most after training, up to 84.22 by 54.94%. Individual factors associated with disparities in the knowledge of hypertension management decreased substantially after training, which included sex, age, education, practice type, professional level, and hierarchy of working institutions. Geographical variations were shown at the provincial level, with the majority of them being explained by factors at the regional level. CONCLUSIONS Accessible web-based training modality, government efforts, accompanied with experiences derived from the training, could be generalized to other low- and middle-income countries in facilitating the hypertension management capacity of LHWs. Localization and evaluation is warranted on the way to its further application. [ABSTRACT FROM AUTHOR]

Hyperlipidemia is a major risk factor for erectile dysfunction (ED). Oxidative stress and phenotypic modulation of corpus cavernosum smooth muscle cells (CCSMCs) are the key pathological factors of ED. N-acetylcysteine (NAC) can inhibit oxidative stress; however, whether NAC can alleviate pathological variations in the corpus cavernosum and promote erectile function recovery in hyperlipidemic rats remains unclear. A hyperlipidemia model was established using 27 eight-week-old male Sprague–Dawley (SD) rats fed a high-fat and high-cholesterol diet (hyperlipidemic rats, HR). In addition, 9 male SD rats were fed a normal diet to serve as controls (NC). HR rats were divided into three groups: HR, HR+normal saline (NS), and HR+NAC (n = 9 for each group; NS or NAC intraperitoneal injections were administered daily for 16 weeks). Subsequently, the lipid profiles, erectile function, oxidative stress, phenotypic modulation markers of CCSMCs, and tissue histology were analyzed. The experimental results revealed that erectile function was significantly impaired in the HR and HR + NS groups, but enhanced in the HR + NAC group. Abnormal lipid levels, over-activated oxidative stress, and multi-organ lesions observed in the HR and HR + NS groups were improved in the HR + NAC group. Moreover, the HR group showed significant phenotypic modulation of CCSMCs, which was also inhibited by NAC treatment. This report focuses on the therapeutic effect of NAC in restoring erectile function using a hyperlipidemic rat model by preventing CCSMC phenotypic modulation and attenuating oxidative stress. [ABSTRACT FROM AUTHOR]

Background: Lung adenocarcinoma (LUAD) is the major subtype of lung cancer and has a poor prognosis. Disulfidptosis is a novel regulated cell death form characterized by aberrant disulfide stress and actin network collapse. This study aimed to identify disulfidptosis-related lncRNAs, and predict LUAD patients’ prognosis and response to antitumor therapies by establishing a disulfidptosisrelated lncRNA model. Methods: Transcriptome and clinical data of LUAD patients were obtained from the TCGA database. Pearson correlation and Cox regression analysis was used to identify disulfidptosis-related lncRNAs associated with overall survival. LASSO regression analysis was adopted to construct the prognostic model. GO, KEGG and GSEA analysis was used to identify cellular pathways related to this model. Immune cell infiltration was investigated by ESTIMATE and CIBERSORT algorithms. Tumor mutational burden (TMB) and its association with modelderived risk score were analyzed using simple nucleotide variation data. Patients’ response to immunotherapy and other antineoplastic drugs was predicted by the TIDE algorithm and GDSC tool, respectively. Results: We identified 127 disulfidptosis-related lncRNAs, and a prognostic model that consists eight of them (KTN1-AS1, AL365181.3, MANCR, LINC01352, AC090559.1, AC093673.1, AP001094.3, and MHENCR) was established and verified. The prognostic model could stratify LUAD patients into two distinct risk-score groups. A high risk score was an independent prognosis factor indicating poor overall survival, and correlated with reduced immune cell infiltration, high TMB, and lower activity of tumor immune response. Immune checkpoint blockade might bring more survival benefits to the high-risk LUAD patients, whereas low-risk patients might be more responsive to targeted therapy and diverse kinase inhibitors. Conclusion: We established a disulfidptosis-related lncRNA model that can be exploited to predict the prognosis, tumor mutational burden, immune cell infiltration landscape, and response to immunotherapy and targeted therapy in LUAD patients. [ABSTRACT FROM AUTHOR]

Doxorubicin is one of the most classical chemotherapeutic drugs for the treatment of cancer. However, resistance to the cytotoxic effects of doxorubicin in tumor cells remains a major obstacle. Aberrant expression of long non-coding RNAs (lncRNAs) has been associated with tumorigenesis and development via regulation of chromatin remodeling, transcription, and posttranscriptional processing. Emerging studies have also revealed that dysregulation of lncRNAs mediates the development of drug resistance through multiple molecules and pathways. In this review, we focus on the role and mechanism of lncRNAs in the progress of doxorubicin resistance in various cancers, which mainly include cellular drug transport, cell cycle disorder, anti-apoptosis, epithelial-mesenchymal transition, cancer stem cells, autophagy, tumor microenvironment, metabolic reprogramming and signaling pathways. This review is aimed to provide potential therapeutic targets for future cancer therapy, especially for the reversal of chemoresistance. [ABSTRACT FROM AUTHOR]

Small bowel adenocarcinoma (SBA), particularly duodenal adenocarcinoma (DA), is a rare gastrointestinal cancer with a dismal prognosis. Data on SBA treatments are limited, and the therapeutic strategy remains uncertain. Currently, chemotherapy is the most used treatment; however, it has a poor median progression-free survival (mPFS) of no more than five months in the second-line setting. We report a case with DA that responded well to the immune checkpoint inhibitor (ICI) tislelizumab plus irinotecan in the secondline treatment. To our knowledge, this is the first report of administering ICIs plus chemotherapy to SBA. Despite the absence of microsatellite instability-high (MSI-H) and high tumor mutational burden (TMB), the patient with TP53/KRAS mutation achieved a significantly long PFS of 17 months, and the benefit is still ongoing. The mechanism of this remarkable efficacy might be associated with an increase in tumor immunogenicity after chemotherapy. The current study presents a promising effect of ICIs plus chemotherapy on SBA, affirming the need to investigate the clinical value of this combination in SBA and the underlying mechanism behind it. [ABSTRACT FROM AUTHOR]

BACKGROUND: Epidemiologic studies have explored the association between a single cardiovascular risk factor (CVRF) and resting heart rate (RHR), but the research on the relation of multiple risk factors with RHR remains scarce. This study aimed to explore the associations between CVRFs clustering and the risk of elevated RHR. METHODS: In this cross-sectional study, adults aged 35-75 years from 31 provinces were recruited by the China PEACE Million Persons Projects from September 2015 to August 2020. We focused on seven risk factors: hypertension, diabetes mellitus, dyslipidemia, obesity, smoking, alcohol use, and low physical activity. Multivariate logistic regression was used to calculate odds ratios (OR) for elevated RHR (> 80 beats/min). RESULTS: Among 1,045,405 participants, the mean age was 55.67 ± 9.86 years, and 60.4% of participants were women. The OR (95% CI) for elevated RHR for the groups with 1, 2, 3, 4 and ≥ 5 risk factor were 1.11 (1.08-1.13), 1.36 (1.33-1.39), 1.68 (1.64-1.72), 2.01 (1.96-2.07) and 2.58 (2.50-2.67), respectively (Ptrend < 0.001). The association between the CVRFs clustering number and elevated RHR was much more pronounced in young males than in other age-sex subgroups. Clusters comprising more metabolic risk factors were associated with a higher risk of elevated RHR than those comprising more behavioral risk factors. CONCLUSIONS: There was a significant positive association between the CVRFs clustering number and the risk of elevated RHR, particularly in young males. Compared clusters comprising more behavioral risk factors, clusters comprising more metabolic risk factors were associated with a higher risk of [ABSTRACT FROM AUTHOR]

Objective: Tricuspid regurgitation (TR) is a common valvular heart disease with unsatisfactory medical therapeutics and high surgical mortality. The present study aims to evaluate the safety and effectiveness of transcatheter tricuspid valve replacement (TTVR) in high-risk patients with severe TR.Methods: This was a compassionate multicentre study. Between September 2018 and November 2019, 46 patients with TR who were not suitable for surgery received compassionate TTVR under general anaesthesia and the guidance of trans-oesophageal echocardiography and fluoroscopy in four institutions. Access to the tricuspid valve was obtained via a minimally invasive thoracotomy and transatrial approach. Patients' data at baseline, before discharge, 30 days and 6 months after the procedure were collected.Results: All patients had severe TR with vena contracta width of 12.6 (11.0, 14.5) mm. Procedural success (97.8%) was achieved in all but one case with right ventricle perforation. The procedural time was 150.0 (118.8, 180.0) min. Intensive care unit time was 2.0 (1.0, 4.0) days. 6-month mortality was 17.4%. Device migration occurred in one patient (2.4%) during follow-up. Transthoracic echocardiography at 6 months after operation showed TR was significantly reduced (none/trivial in 33, mild in 4 and moderate in 1) and the primary safety end point was achieved in 38 cases (82.6%). Patients suffered from peripheral oedema and ascites decreased from 100.0% and 47.8% at baseline to 2.6% and 0.0% at 6 months.Conclusions: The present study showed TTVR was feasible, safe and with low complication rates in patients with severe TR. [ABSTRACT FROM AUTHOR]

OBJECTIVE To assess the association between beta-blockers and 1-year clinical outcomes in heart failure (HF) patients with atrial fibrillation (AF), and further explore this association that differs by left ventricular ejection fraction (LVEF) level. METHODS We enrolled hospitalized HF patients with AF from China Patient-centered Evaluative Assessment of Cardiac Events Prospective Heart Failure Study. COX proportional hazard regression models were employed to calculate hazard ratio of betablockers. The primary outcome was all-cause death. RESULTS Among 1 762 HF patients with AF (756 women [41.4%]), 1 041 (56%) received beta-blockers at discharge and 1 272 (72.2%) had an LVEF > 40%. During one year follow up, all-cause death occurred in 305 (17.3%), cardiovascular death occurred in 203 patients (11.5%), and rehospitalizations for HF occurred in 622 patients (35.2%). After adjusting for demographic characteristics, social economic status, smoking status, medical history, anthropometric characteristics, and medications used at discharge, the use of beta-blockers at discharge was not associated with all-cause death [hazard ratio (HR): 0.86; 95% Confidence Interval (CI): 0.65-1.12; P = 0.256], cardiovascular death (HR: 0.76, 95% CI: 0.52-1.11; P = 0.160), or the composite outcome of all-cause death and HF rehospitalization (HR: 0.97, 95% CI: 0.82-1.14; P = 0.687) in the entire cohort. There were no significant interactions between use of beta-blockers at discharge and LVEF with respect to all-cause death, cardiovascular death, or composite outcome. In the adjusted models, the use of beta-blockers at discharge was not associated with all-cause death, cardiovascular death, or composite outcome across the different levels of LVEF: reduced (< 40%), mid-range (40%-49%), or preserved LVEF (= 50%). CONCLUSION Among HF patients with AF, the use of beta-blockers at discharge was not associated with 1-year clinical outcomes, regardless of LVEF. [ABSTRACT FROM AUTHOR]

Background: Preeclampsia (PE) is a severe pregnancy complication and is an important cause for maternal and child death, premature delivery, and limited intrauterine growth and development. The aim of this study was to investigate the role of NGAL and cystatin C, alone and in combination, for early prediction of PE at 10 - 14 weeks of gestation. Methods: Serum levels of NGAL and cystatin C were assessed in women at 10 - 14 weeks of gestation who subsequently developed PE (n = 128) and normal pregnancy outcome (n = 183). Comparison of clinical characteristics, NGAL, and cystatin C levels between normal pregnancy and PE groups were analyzed using Mann-Whitney test. The receiver operating characteristic curve (ROC curve) was used to analyze the value of serum NGAL and cystatin C levels in predicting PE. Results: The levels of cystatin C and NGAL in the serum were significantly higher in the PE group [0.64 mg/L (0.52 - 0.78)] and [34.9 ng/mL (24.4 - 55.2), respectively] than in the normal pregnancy group [0.56 mg/L (0.49 - 0.65)] and [20.2 ng/mL (13.8 - 26.9), respectively]. ROC curve analysis showed that serum NGAL levels predicted the area under the curve in the PE period 0.739 (95% CI: 0.618 to 0.860). Serum cystatin C levels predicted the area under the curve in the PE period 0.722 (95% CI: 0.592 to 0.853). The combination of serum NGAL and cystatin C levels predicted the area under the curve in the PE period 0.877 (95% CI: 0.811 to 0.943). Conclusions: NGAL and cystatin C levels in serum appear to be ideal biomarkers for PE prediction at 10 - 14 weeks. The combination of NGAL and cystatin C will also be more valuable in discriminating patients at risk of developing PE from other pregnancy complications early in gestation. [ABSTRACT FROM AUTHOR]

Bile duct hamartoma (BDH) is a rare liver disease with a rising incidence in recent years. A retrospective study on BDH patients between June 2007 and December 2015 was conducted. All the medical records, including clinical, imaging and pathological characteristics, were retrieved. Follow-up data were obtained by telephone communication. The majority of the patients had no symptoms and the laboratory tests were normal. The appearance on ultrasound examination was variable. The lesion exhibited low density on plain computed tomography and no enhancement in 4 cases, and inhomogeneous enhancement in 1 case. Magnetic resonance imaging examination revealed hypointensity on T1-weighted imaging (WI), hyperintensity on T2WI, no enhancement in 1 case, and enhancement in 4 cases. Two patients underwent magnetic resonance cholangiopancreatography due to jaundice and intrahepatic bile duct dilation. The preoperative diagnosis was liver cancer in 4 cases, hepatic hilar biliary obstruction in 1, chronic calculous cholecystitis in 1, suspected hepatic abscess in 1, and benign liver tumor in 2 cases. All the patients underwent surgery. Nest-like cell arrangements were observed in 2 patients, and in 1 patient the lesion transformed to intrahepatic cholangiocarcinoma, resulting in the patient's death 25 months after surgery. Thus, BDH may transform into a life-threatening cholangiocarcinoma and it should be surgically removed. Furthermore, the mechanism underlying carcinogenesis in BDH requires further investigation. [ABSTRACT FROM AUTHOR]

The present study aimed to determine the diagnostic concordance of plasma epidermal growth factor receptor (EGFR) mutation using droplet digital polymerase chain reaction (ddPCR) with tumor tissue samples and the predictive clinical significance of plasma EGFR mutation concentration. Plasma DNA samples from patients with non-small cell lung cancer (NSCLC) were analyzed for EGFR exon 21 codon 858 (L858R) mutation, deletion of exon 19 (ex19del) and exon 20 codon 790 (T790M) mutation using ddPCR. Firstly, the mutations in the plasma samples were compared with the matched tumor samples to determine the concordance. Secondly, image examination follow-ups were analyzed to assess the association between plasma EGFR mutation concentration and patients' response to EGFR-tyrosine kinase inhibitors (TKIs). A total of 51 patients with NSCLC were enrolled, including 48 newly diagnosed patients. Compared with tumor tissue samples, the sensitivity and specificity of ddPCR were 76.19% (16/21) and 96.55% (28/29) for mutant L858R, and 88.89% (8/9) and 100% (41/41) for ex19del, respectively. No patient exhibited the T790M mutation in the tumor tissue or plasma samples. Furthermore, 5 patients with the L858R mutation and 4 patients with ex19del in plasma and tumor tissue samples had been followed up with image examination for ≥3 months following EGFR-TKI treatment. The baseline mutant EGFR concentrations were positively correlated with a reduction in tumor burden (Spearman's r=0.7000, P=0.0358). When analyzed separately, ex19del concentrations (Spearman's r=1.0000, P<0.0001) were also positively correlated with the reduction, while mutant L858R concentrations were not (Spearman's r=0.7000, P=0.1881). In the present study, detection of plasma EGFR mutations using ddPCR exhibited sufficient concordance with tumor tissue sample results. Baseline plasma mutant EGFR and ex19del concentrations were significantly and positively correlated with response to EGFR-TKIs. [ABSTRACT FROM AUTHOR]

Progress in the treatment options for small cell lung cancer (SCLC) remains poor. Concerns exist regarding the efficacy of bevacizumab in SCLC. The present study aimed to evaluate the efficacy of bevacizumab in extensive stage (ES)‑SCLC. A meta‑analysis on studies conducted and listed on the Medline, Cochrane Trials, ASCO, ESMO and Clinical-Trial databases, and Chinese databases prior to April 2015 was performed. All clinical trials in which patients with ES‑SCLC were treated with bevacizumab were considered. Survival rates at specific time points were extracted from the reported survival curves. Hazard ratios (HR) for progression‑free survival (PFS) and overall survival (OS), rates for PFS, OS, overall response rate (ORR), and side‑effects were synthesized using random‑effects or fixed‑effects model. Two randomized control trials (RCT) (176 patients) and six single‑arm trials (292 patients) were identified. In RCTs, no statistically significant differences were observed in PFS [HR, 0.70; 95% confidence interval (CI), 0.41‑1.19; P=0.19] or OS (HR, 1.21; 95% CI, 0.84‑1.75; P=0.31). In the first‑line trials, pooled 6‑month and 1‑year PFS rates were 57% (95% CI, 39‑76%) and 10% (95% CI, 4‑16%), respectively. Synthesized 1‑year and 2‑year OS rates were 45% (95% CI, 36‑54%) and 10% (95% CI, 6‑14%), respectively. Reported median PFS and OS times for pretreated patients were 2.7‑4.0 months and 6.3‑7.4 months, respectively. Pooled ORRs were 71% (95% CI, 59‑82%) in the first‑line trials and 18% (95% CI, 11‑25%) in the second‑line trials. The most common types of reported toxicities were chemotherapy‑associated, including neutropenia, leukopenia, fatigue and thrombocytopenia. According to the RCTs, bevacizumab did not appear to improve the PFS or OS for patients with ES‑SCLC, with low quality of evidence. Due to the disappointing pooled efficacy in the single‑arm trials, more clinical studies on bevacizumab in SCLC may not be valuable, although the evidence was with low quality. [ABSTRACT FROM AUTHOR]

Stem cell transplantation and low-energy shock-wave therapy (LESWT) have emerged as potential and effective treatment protocols for diabetic erectile dysfunction. During the tracking of transplanted stem cells in diabetic erectile dysfunction models, the number of visible stem cells was rather low and decreased quickly. LESWT could recruit endogenous stem cells to the cavernous body and improve the microenvironment in diabetic cavernous tissue. Thus, we deduced that LESWT might benefit transplanted stem cell survival and improve the effects of stem cell transplantation. In this research, 42 streptozotocin-induced diabetic rats were randomized into four groups: the diabetic group (n = 6), the LESWT group (n = 6), the bone marrow-derived mesenchymal stem cell (BMSC) transplantation group (n = 15), and the combination of LESWT and BMSC transplantation group (n = 15). One and three days after BMSC transplantation, three rats were randomly chosen to observe the survival numbers of BMSCs in the cavernous body. Four weeks after BMSC transplantation, the following parameters were assessed: the surviving number of transplanted BMSCs in the cavernous tissue, erectile function, real-time polymerase chain reaction, and penile immunohistochemical assessment. Our research found that LESWT favored the survival of transplanted BMSCs in the cavernous body, which might be related to increased stromal cell-derived factor-1 expression and the enhancement of angiogenesis in the diabetic cavernous tissue. The combination of LESWT and BMSC transplantation could improve the erectile function of diabetic erectile function rats more effectively than LESWT or BMSC transplantation performed alone. [ABSTRACT FROM AUTHOR]

We present a novel numerical model and simulate preliminarily the charging process of a polymer subjected to electron irradiation of several 10 keV. The model includes the simultaneous processes of electron scattering and ambipolar transport and the influence of a self-consistent electric field on the scattering distribution of electrons. The dynamic spatial distribution of charges is obtained and validated by existing experimental data. Our simulations show that excess negative charges are concentrated near the edge of the electron range. However, the formed region of high charge density may extend to the surface and bottom of a kapton sample, due to the effects of the electric field on electron scattering and charge transport, respectively. Charge trapping is then demonstrated to significantly influence the charge motion. The charge distribution can be extended to the bottom as the trap density decreases. Charge accumulation is therefore balanced by the appearance and increase of leakage current. Accordingly, our model and numerical simulation provide a comprehensive insight into the charging dynamics of a polymer irradiated by electrons in the complex space environment. [ABSTRACT FROM AUTHOR]

The A-band resonance Raman spectra of thiourea were obtained in water and acetonitrile solution. B3LYP/6-311++G(3df,3pd) and RCIS/6-311++G(3df,3pd) calculations were done to elucidate the ultraviolet electronic transitions, the distorted geometry structure and the saddle point of thiourea in 21A excited state, respectively. The resonance Raman spectra were assigned. The absorption spectrum and resonance Raman intensities were modeled using Heller's time-dependent wave packet approach to resonance Raman scattering. The results indicate that largest change in the displacement takes place with the C=S stretch mode v6 (ǀΔǀ=0.95) and noticeable changes appear in the H5N3H6+H8N4H7 wag v5 (ǀΔǀ=0.19), NCN symmetric stretch+C=S stretch+N3H6+H8N4 wag v4 (ǀΔǀ=0.18), while the moderate intensities of 2v15 and 4v15 are mostly due to the large excited state frequency changes of v15, but not due to its significant change in the normal mode displacement. The mechanism of the appearance of even overtones of the S=CN2 out of plane deformation is explored. The results indicate that a Franck-Condon region saddle point is the driving force for the quadric phonon mechanism within the standard A-term of resonance Raman scattering, which leads to the pyramidalization of the carbon center and the geometry distortion of thiourea molecule in 21A excited state. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effect of pulsatile flow on cerebral blood flow (CBF) in infants with the use of a mild hypothermic cardiopulmonary bypass (CPB). Thirty infants scheduled for open heart surgery were randomized to the pulsatile group (Group P, n = 15) and nonpulsatile group (Group NP, n = 15). In Group P, pulsatile perfusion was applied during the aortic cross-clamping period, whereas nonpulsatile perfusion was used in Group NP. The systolic peak velocity (Vs), the end of diastolic velocity (Vd), the mean velocity (Vm), and the pulsatility index (PI) and the resistance index (RI) of the middle cerebral artery were measured by a transcranial Doppler (TCD) ultrasound after anesthesia (T1; baseline), at the beginning of CPB (T2), 10 min after aortic cross-clamping (T3), 3 min after declamping (T4), at the cessation of CPB (T5), and at the end of the operation (T6). During T3 and T4, the Vs in Group P was significantly higher than in Group NP. However, there were no statistically significant differences between Vd and Vm. The PI and RI in Group P were also higher than those in Group NP (both P < 0.05). During T5, Vd and Vm were higher in Group P ( P < 0.05), whereas there was no difference in Vs. Additionally, PI and RI in Group P were significantly lower than those in Group NP ( P < 0.05). However, there was no difference during T6. Pulsatile perfusion may increase CBF and decrease cerebral vascular resistance in the early period after mild hypothermic CPB. [ABSTRACT FROM AUTHOR]

We present the top–bottom effect (TBE) of a 5 µm thick amorphous specimen in a 3 MV ultrahigh voltage electron microscope (ultra-HVEM) and its influence on the quality of electron tomography (ET). The 40-nm gold particles on the top surface of the specimen tilted at different angles have been observed to be of poorer image quality than those on the symmetrical bottom surface obtained by tilting and turning over the specimen. The point spread function of the gold-particle images was calculated using the increment Wiener filter and the image-quality variation was then evaluated. The TBE is shown to become more remarkable with the increase of the effective thickness of the tilted specimen or the decrease of the magnification of the ultra-HVEM. The ET simulation indicates that the TBE may generate ∼4% distortion in the radial direction of a reconstructed sphere model. [ABSTRACT FROM AUTHOR]

Net photosynthetic rates (Pns) in leaves were compared between rice plants grown in ambient air control and free-air CO2 enrichment (FACE, about 200 µmol mol–1 above ambient) treatment rings. When measured at the same CO2 concentration, the Pn of FACE leaves decreased significantly, indicating that photosynthetic acclimation to high CO2 occurs. Although stomatal conductance (Gs) in FACE leaves was markedly decreased, intercellular CO2 concentrations (Ci) were almost the same in FACE and ambient leaves, indicating that the photosynthetic acclimation is not caused by the decreased Gs. Furthermore, carboxylation efficiency and maximal Pn, both light and CO2-saturated Pn, were decreased in FACE leaves, as shown by the Pn–Ci curves. In addition, the soluble protein, Rubisco (ribulose-1,5-bisphosphate caboxylase/oxygenase), and its activase contents as well as the sucrose-phosphate synthase activity decreased significantly, while some soluble sugar, inorganic phosphate, chlorophyll and light-harvesting complex II (LHC II) contents increased in FACE leaves. It appears that the photosynthetic acclimation in rice leaves is related to both ribulose-1,5-bisphosphate (RuBP) carboxylation limitation and RuBP regeneration limitation. [ABSTRACT FROM AUTHOR]

From the 40 nm gold particles on the surface of a 5 μm thick amorphous specimen tilted by a 360° tilt holder, we have observed the top–bottom effect (TBE) in a 3 MV ultrahigh-voltage electron microscope. Because of the TBE, object points located on the top surface of the specimen have poorer image quality than those on the bottom. Measurements of the diameter and contrast of gold-particle images show that the TBE becomes strong when increasing the effective thickness of the specimen by tilting the specimen. The TBE can produce additional image blurring of about 10, 27, and 74 nm in the gold-particle diameter for the effective thickness of 5.0, 10.0, and 14.6 μm, respectively. The need for further investigations is thus suggested to understand and determine the TBE limitation on the resolution or fidelity of electron tomography for thick specimens. [ABSTRACT FROM AUTHOR]

In electron tomography (ET) based on a transmission electron microscope, the effective thickness of a specimen increases with the tilt angle and, therefore, the projection quality may deteriorate because of electron scattering. The information-missing region, however, can be reduced by broadening the specimen tilt range. To clarify the general influence of these effects on ET, the projection quality varying with the tilt angle was quantitatively evaluated for a 5-μm thick specimen observed with a 3 MV ultrahigh-voltage electron microscope. Simulations of three-dimensional reconstruction were then performed for different specimen thicknesses and tilt ranges. As a result, the ET accuracy was shown to decrease as the specimen thickness increased. However, an optimumspecimen-tilt range, at which ET could reach its highest accuracy, was found to exist and become small with the increase of the specimen thickness. The presented results are helpful for determining the specimen thickness limitation on the ET resolution and improving the ET fidelity of thick specimens. [ABSTRACT FROM AUTHOR]

The charging effect of an insulating specimen from electron beam (e-beam) irradiation may be utilized to facilitate imaging in the scanning electron microscope (SEM). This has been confirmed by a great deal of experimental work during the last three decades. Particularly, recent investigations indicate that even located underneath insulating thin films that a low energy e-beam cannot penetrate, conductors not biased and overlay marks, are observable through a novel imaging pattern, charging contrast. Unlike conventional SEM contrasts, which usually reflect surface characteristics, the dynamic charging contrast can reveal information of underlying structures without any external exciting signal. The authors consider that this kind of charging contrast arises from the different redistribution rates of secondary electrons returning to the surface under the surface local field of the charged specimen. The charging contrast has the prospect of extending the SEM application and forming new testing methods matched with the fast development of integrated circuits. [ABSTRACT FROM AUTHOR]

A one-dimensional model is proposed for analysing static capacitance contrast (SCC) in scanning electron microscopy. For the large-scale integrated specimen covered by an insulating thin film, the imaging signal is calculated considering the redistribution of secondary electrons (SEs) and the charging process of the equivalent effective capacitance between the irradiation point and substrate. The calculated SCC as a function of the irradiation charge density is in good agreement with the experimental SCC. It is confirmed that the SCC arises from the redistribution of SEs and the difference in the effective capacitance of irradiation points under the condition of positive charging. [ABSTRACT FROM AUTHOR]

We report on a simple and effective charge neutralization method for measuring the total electron induced secondary electron yield of insulators in a measurement system with a single pulsed electron gun. In this method, the secondary electron collector is negatively biased with respect to the sample to force some emitted secondary electrons to return to the sample surface and therefore to neutralize positive charges accumulated in the sample during the previous measurement. The adequate negative bias is determined and the equilibrium state of negative charging is discussed. The efficacy of the method is demonstrated by the measured electron yields in the cases with and without charge neutralization and by comparison with existing electron yield data of polyimide. [ABSTRACT FROM AUTHOR]

Objective: To observe the therapeutic efficacy of puncturing Neiguan (PC 6) and Zusanli (ST 36) on chemotherapy-related nausea and vomiting. Methods: In addition to the routine intervention for vomiting, the 26 malignant cancer patients after the platinum-involved chemotherapy were punctured at bilateral Zusanli (ST 36) and Neiguan (PC 6) twice a day before the chemotherapy lasting until 3 days after the chemotherapy, each treatment lasting 30 min. All the patients were adopted the self-comparison approach, i.e., the needling therapy was used either in the first or the second treatment course. Results: As far as the acupuncture treatment group is concerned, 15 cases got nausea and vomiting, including 6 cases of Io, 5 cases of IIo, 2 cases of IIIo and no reaction of IVo, 11 cases of acute vomiting, 4 cases of delayed vomiting and no case of premature vomiting; while as far as the control group is concerned, 19 cases got nausea and vomiting, including 5 cases of Io, 9 cases of IIo, 4 cases of IIIo and 1 case of IVo, 13 cases of acute vomiting, 6 cases of delayed vomiting and no case of premature vomiting. The vomiting occurrence rate and degree in the treatment group were both lower than that of the control group (57.7%vs 73.1%, P<0.01) and the patients in the treatment group had an improved life quality. Conclusion: Puncturing the bilateral Zusanli (ST 36) and Neiguan (PC 6) can reduce the gastrointestinal reaction to platinum-involved chemotherapy project and improve the patients’ life quality. [ABSTRACT FROM AUTHOR]

Acne is divided into the patterns of wind and heat in the lung meridian and accumulation of dampness and heat. Forty cases of acne were treated by acupuncture plus herbal drugs (acupuncture and drug group, A) and 30 cases were treated by simple acupuncture as the control group (acupuncture group, B). The results showed basic cure in 31 cases, remarkable effect in 5 cases, effect in 3 cases, failure in 1 case and the total effective rate of 97.5% in Group A, and basic cure in 16 cases, remarkable effect in 6 cases, effect in 3 cases, failure in 5 cases and the total effective rate of 83. 3% in Group B. There was no significant difference ( P>0.05) in the therapeutic effect and there was a significant difference ( P<0.01) in the curative rate in the two groups. The therapeutic effect was obviously better in Group A than in Group B. [ABSTRACT FROM AUTHOR]

We clarify the scanning electron microscopic contrast mechanism for imaging a buried SiO2 trench microstructure with interface trapped charges by simulating both electron scattering and transport. Here, the interface trapped charges make the SiO2 film more negatively charged and increase excess holes in the space charge distribution of the electron scattering region. The generated positive surface electric field thus redistributes some emitted secondary electrons and results in the dark contrast. This contrast mechanism is validated by comparing with experiments, and it may also provide an interesting approach for imaging and detecting deep interface trapped charges in insulating films. [ABSTRACT FROM AUTHOR]

Electron transmission through tilted epoxy-resin film specimens with thicknesses of 1 and 5 μm has been measured under different accelerating voltages and diameters of the objective aperture in a 3 MV ultrahigh voltage electron microscope. Measurements show that the linearity between the logarithmic electron transmission and effective thickness of the tilted specimens holds valid only for some smaller effective thicknesses. However, the higher accelerating voltage leads to a wider linear attenuation range. The linear range can reach 7 μm for the 3 MeV incident electrons. Moreover, the measurements were analyzed with the electron-scattering theory. Actually, the high-energy electrons are capable of penetrating much thicker specimens, but many electrons elastically scattered at large angles cannot be collected as useful signals because of being blocked by the objective aperture in the mode of amplitude contrast. The need for further investigations was suggested to determine theoretically the electron transmission through a thick low-Z specimen and its exponential attenuation range. [ABSTRACT FROM AUTHOR]