Convolutional neural network assistance significantly improves dermatologists' diagnosis of cutaneous tumours using clinical images.

BACKGROUND: Convolutional neural networks (CNNs) have demonstrated expert-level performance in cutaneous tumour classification using clinical images, but most previous studies have focused on dermatologist-versus-CNN comparisons rather than their combination. The objective of our study was to evaluate the potential impact of CNN assistance on dermatologists for clinical image interpretation. METHODS: A multi-class CNN was trained and validated using a dataset of 25,773 clinical images comprising 10 categories of cutaneous tumours. The CNN's performance was tested on an independent dataset of 2107 images. A total of 400 images (40 per category) were randomly selected from the test dataset. A fully crossed, self-control, multi-reader multi-case (MRMC) study was conducted to compare the performance of 18 board-certified dermatologists (experience: 13/18 ≤ 10 years; 5/18＞10 years) in interpreting the 400 clinical images with or without CNN assistance. RESULTS: The CNN achieved an overall accuracy of 78.45% and kappa of 0.73 in the classification of 10 types of cutaneous tumours on 2107 images. CNN-assisted dermatologists achieved a higher accuracy (76.60% vs. 62.78%, P < 0.001) and kappa (0.74 vs. 0.59, P < 0.001) than unassisted dermatologists in interpreting the 400 clinical images. Dermatologists with less experience benefited more from CNN assistance. At the binary classification level (malignant or benign), the sensitivity (89.56% vs. 83.21%, P < 0.001) and specificity (87.90% vs. 80.92%, P < 0.001) of dermatologists with CNN assistance were also significantly improved than those without. CONCLUSIONS: CNN assistance improved dermatologist accuracy in interpreting cutaneous tumours and could further boost the acceptance of this new technique.

Aggressive Angiomyxoma in the Scrotum: A Case Series and Literature Review.

Purpose: Aggressive angiomyxoma (AAM) was identified as a distinct clinicopathological entity in 1983. Since then, a few cases of its occurrence in the scrotum have been reported. This case series was performed to increase clinicians' understanding of the clinical features and treatment of AAM in the scrotum. Methods: We evaluated the clinical presentations, treatments, and follow-up of two patients with AAM in the scrotum in our hospital and 34 cases reported in the literature. Results: Among the 36 patients, the average age was 48.3 ± 20.6 years old (range from 1 to 81); the average maximum diameter of the tumor was 8.36 cm (1.6-25 cm); the site of one (2.78%) patient was located in the epididymis, two (5.56%) in the testes, five (13.89%) in the spermatic cord, and 28 (77.77%) in the scrotum. The clinical symptoms were generally non-specific and 20 patients inadvertently discovered their slow-growing painless masses. The treatments for all these patients were surgical excision once the tumor had been found and one case underwent excision followed by radiotherapy. The median follow-up time for the remaining 32 cases was 24.5 months (1 to 84 months). Recurrence occurred in three cases (9.09%) at the primary sites and no cases of distant metastasis. Conclusion: AAM of the scrotum can occur in middle-aged and elderly men. The clinical manifestation generally involves a long history of asymptomatic masses or swelling in the scrotum. Ultrasound is the most commonly used diagnostic technique but magnetic resonance imaging may be more effective. The mainly treatment is surgical excision and postoperative histopathological examination is still the gold standard for its diagnosis. Although it is locally aggressive, metastasis is extremely rare in males.

Development of a droplet digital PCR for detection and quantification of porcine epidemic diarrhea virus.

Porcine epidemic diarrhea, a disease caused by porcine epidemic diarrhea virus (PEDV), results in large economic losses to the global swine industry. To manage this disease effectively, it is essential to detect PEDV early and accurately. We developed a sensitive and accurate droplet digital PCR (ddPCR) assay to detect PEDV. The optimal primer-to-probe concentration and melting temperature were identified as 300:200 nM and 59.2°C, respectively. The specificity of the ddPCR assay was confirmed by negative test results for common swine pathogens. The detection limit for the ddPCR was 0.26 copies/µL, which is a 5.7-fold increase in sensitivity compared to that of real-time PCR (rtPCR). Both ddPCR and rtPCR assays exhibited good linearity, although ddPCR provided higher sensitivity for clinical detection compared to that of rtPCR. Our ddPCR methodology provides a promising tool for evaluating the PEDV viral load when used for clinical testing, particularly for detecting samples with low-copy viral loads.

Hydrogen Sulfide Alleviates Aluminum Toxicity via Decreasing Apoplast and Symplast Al Contents in Rice.

Hydrogen sulfide (H2S) plays a vital role in Al3+ stress resistance in plants, but the underlying mechanism is unclear. In the present study, pretreatment with 2 µM of the H2S donor NaHS significantly alleviated the inhibition of root elongation caused by Al toxicity in rice roots, which was accompanied by a decrease in Al contents in root tips under 50 µM Al3+ treatment. NaHS pretreatment decreased the negative charge in cell walls by reducing the activity of pectin methylesterase and decreasing the pectin and hemicellulose contents in rice roots. This treatment also masked Al-binding sites in the cell wall by upregulating the expression of OsSATR1 and OsSTAR2 in roots and reduced Al binding in the cell wall by stimulating the expression of the citrate acid exudation gene OsFRDL4 and increasing the secretion of citrate acid. In addition, NaHS pretreatment decreased the symplasmic Al content by downregulating the expression of OsNRAT1, and increasing the translocation of cytoplasmic Al to the vacuole via upregulating the expression of OsALS1. The increment of antioxidant enzyme [superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT), and peroxidase (POD)] activity with NaHS pretreatment significantly decreased the MDA and H2O2 content in rice roots, thereby reducing the damage of Al3+ toxicity on membrane integrity in rice. H2S exhibits crosstalk with nitric oxide (NO) in response to Al toxicity, and through reducing NO content in root tips to alleviate Al toxicity. Together, this study establishes that H2S alleviates Al toxicity by decreasing the Al content in the apoplast and symplast of rice roots.

Treatment of upper tract urothelial carcinoma with ureteroscopy and thulium laser: a retrospective single center study.

BACKGROUND: Treatment with the combination of ureteroscopy and thulium laser ablation may provide an alternative to radical nephroureterectomy (RNU) for patients with upper tract urothelial carcinoma (UTUC). The purpose of this study was to investigate the efficacy and safety of this technique. METHODS: We performed a retrospective review of the data for patients who were treated surgically for upper tract urothelial carcinoma in a single center. It included 32 patients treated by endoscopic thulium laser resection and 107 patients treated by radical nephroureterectomy (RNU). We compared the data of patient sex, age at diagnosis, location of carcinoma, length of hospitalization, tumor site, size, grade, recurrence, preoperative creatinine and postoperative creatinine in two groups. Patients were examined by ureteroscopy every 3 months during the first year after surgery, then every 6 months each year. RESULTS: All 32 patients were treated successfully, among which 6 were operated by a flexible ureteroscope. The average tumor size was 13 ± 7 mm in diameter. The tumor was rated as low grade in 27 patients and high grade in 5 patients. Ureteral stricture developed in 4 patients 3 months later after surgery, but the stricture was succesfully treated through endoscopic dilation. Seven patients had tumor recurrence, 3 of which underwent nephroureterectomy during the follow-up. Postoperative creatinine levels (umol/L) were respectively 89 ± 7.5 in laser group and 123 ± 15.4 in RNU group (p < 0.01). Length of hospitalization was respectively 3.6 ± 1.9 and 8.6 ± 2.4 days (p < 0.01). Local or bladder recurrence rate of thulium laser group and RNU group was respectively 21.9 and 13.1% (p < 0.01). CONCLUSIONS: Thulium laser group is associated with a less loss of renal function, a shorter length of hospitalization, but a higher rate of tumor recurrence. Thulium laser therapy combined with ureteroscopic treatment can be considered as an acceptable treatment for selected cases of UTUC. Lifetime intensive surveillance is necessary.

miR-141 Inhibits Proliferation and Migration of Colorectal Cancer SW480 Cells.

BACKGROUND: This study was designed to determine the molecular function of miR-141 and the underlying mechanisms in colorectal cancer (CRC). MATERIALS AND METHODS: SW480 cells in which miR-141 was up- or down-regulated were established. Reverse transcription, quantitative polymerase chain reaction and Western blotting were used to examine the microRNA and protein expression. Cell-cycle progression was analyzed by flow cytometry. Proliferation marker Ki-67 was evaluated by immunofluorescence. Transwell assay was conducted to determine the migration rates of cells. Subcutaneous xenograft models were used to examine the effect of miR-141 on tumorigenicity. Human mitogen-activated protein kinase (MAPK) and receptor tyrosine kinase (RTK) pathway phosphorylation array assays were used to interrogate MAPK and RTK pathway activation. RESULTS: miR-141 directly targeted zinc finger E-box-binding homeobox 1/2 (ZEB1/2). We first determined the expression levels of ZEB1 and ZEB2 in miR-141-expressing cells and miR-141-knockdown cells and found that inhibition of miR-141 significantly increased the expression of ZEB2. In vitro study revealed that miR-141 overexpression inhibited the expression of Ki-67. Furthermore, overexpression of miR-141 led to a significant reduction in the proliferation of SW480 cells via induction of cell-cycle arrest at the G1 stage. In contrast, inhibition of miR-141 markedly promoted the proliferation of SW480 cells by promoting cell-cycle progression. Moreover, overexpression of miR-141 significantly inhibited SW480 cell migration in vitro. In addition, overexpression of miR-141 significantly reduced tumor size and weight, and inhibited the growth of SW480 cell-derived tumor in nude mice. Notably, overexpression of miR-141 also suppressed the liver metastasis of SW480 cells in nude mice. Using RTK and MAPK arrays, we found increased phosphorylation of hepatocyte growth factor receptor (HGFR/c-MET) following inhibition of miR-141, but phosphorylation of P53, AKT, ERK1/2, P38 and mTOR, etc., in SW480 cells was not affected by miR-141. CONCLUSION: Our results suggest that miR-141 functions as a tumor suppressor through ZEB2 and HGFR in CRC cells.

Dietary fat alters the response of hypothalamic neuropeptide Y to subsequent energy intake in broiler chickens.

Dietary fat affects appetite and appetite-related peptides in birds and mammals; however, the effect of dietary fat on appetite is still unclear in chickens faced with different energy statuses. Two experiments were conducted to investigate the effects of dietary fat on food intake and hypothalamic neuropeptides in chickens subjected to two feeding states or two diets. In Experiment 1, chickens were fed a high-fat (HF) or low-fat (LF) diet for 35 days, and then subjected to fed (HF-fed, LF-fed) or fasted (HF-fasted, LF-fasted) conditions for 24 h. In Experiment 2, chickens that were fed a HF or LF diet for 35 days were fasted for 24 h and then re-fed with HF (HF-RHF, LF-RHF) or LF (HF-RLF, LF-RLF) diet for 3 h. The results showed that chickens fed a HF diet for 35 days had increased body fat deposition despite decreasing food intake even when the diet was altered during the re-feeding period (P<0.05). LF diet (35 days) promoted agouti-related peptide (AgRP) expression compared with HF diet (P<0.05) under both fed and fasted conditions. LF-RHF chickens had lower neuropeptide Y (NPY) expression compared with LF-RLF chickens; conversely, HF-RHF chickens had higher NPY expression than HF-RLF chickens (P<0.05). These results demonstrate: (1) that HF diet decreases food intake even when the subsequent diet is altered; (2) the orexigenic effect of hypothalamic AgRP; and (3) that dietary fat alters the response of hypothalamic NPY to subsequent energy intake. These findings provide a novel view of the metabolic perturbations associated with long-term dietary fat over-ingestion in chickens.

µSR investigation of a new diluted magnetic semiconductor Li(Zn,Mn,Cu)As with Mn and Cu codoping at the same Zn sites.

We report the successful synthesis and characterization of a new type I-II-V bulk form diluted magnetic semiconductor (DMS) Li(Zn,Mn,Cu)As, in which charge and spin doping are decoupled via (Cu,Zn) and (Mn,Zn) substitution at the same Zn sites. Ferromagnetic transition temperature up to ∼33 K has been observed with a coercive field ∼40 Oe for the 12.5% doping level. µSR measurements confirmed that the magnetic volume fraction reaches nearly 100% at 2 K, and the mechanism responsible for the ferromagnetic interaction in this system is the same as other bulk form DMSs.

Leucine alleviates dexamethasone-induced suppression of muscle protein synthesis via synergy involvement of mTOR and AMPK pathways.

Glucocorticoids (GCs) are negative muscle protein regulators that contribute to the whole-body catabolic state during stress. Mammalian target of rapamycin (mTOR)-signalling pathway, which acts as a central regulator of protein metabolism, can be activated by branched-chain amino acids (BCAA). In the present study, the effect of leucine on the suppression of protein synthesis induced by GCs and the pathway involved were investigated. In vitro experiments were conducted using cultured C2C12 myoblasts to study the effect of GCs on protein synthesis, and the involvement of mTOR pathway was investigated as well. After exposure to dexamethasone (DEX, 100 µmol/l) for 24 h, protein synthesis in muscle cells was significantly suppressed (P<0.05), the phosphorylations of mTOR, ribosomal protein S6 protein kinase 1 (p70s6k1) and eukaryotic initiation factor 4E binding protein 1 (4EBP1) were significantly reduced (P<0.05). Leucine supplementation (5 mmol/l, 10 mmol/l and 15 mmol/l) for 1 h alleviated the suppression of protein synthesis induced by DEX (P<0.05) and was accompanied with the increased phosphorylation of mTOR and decreased phosphorylation of AMPK (P<0.05). Branched-chain amino transferase 2 (BCAT2) mRNA level was not influenced by DEX (P>0.05) but was increased by leucine supplementation at a dose of 5 mmol/l (P<0.05).

Effect of biological behavior and clinical significance of maspin gene on cervical squamous carcinoma SiHa cell.

OBJECTIVE: This study was performed to evaluate the effect of mammary serine protease inhibitor (maspin) overexpression on human cervical squamous carcinoma (SCC) SiHa cell proliferation and apoptosis in vitro. MATERIAL AND METHODS: Recombinant plasmid pcDNA3-maspin was stably transfected into human cervical SCC SiHa cell. Maspin mRNA was determined by RT-PCR, whereas maspin protein was detected by Western blot analysis and immunocytochemistry (IHC). Cell proliferation activity was measured by MTT method. Apoptosis rate and cell cycle distribution were detected by flow cytometry to understand the changes in the cell biological characteristics. RESULTS: The strengthened expression of the maspin gene in the SiHa cell was confirmed by RT-PCR, Western blot, and immunocytochemistry (IHC) (p < 0.05). Suppressed proliferation activity and increased apoptosis rate of SiHa-m (maspin stable transfected) versus SiHa and SiHa-vector cell (SiHa-pc3) were shown by MTT and flow cytometry (p < 0.05). SiHa and SiHa-pc3-had no statistical significance (p > 0.05). CONCLUSION: The results showed that maspin gene can significantly inhibit human cervical SCC SiHa cell proliferation and effectively slow cancer growth. Maspin may be a new molecular target in the gene therapy of human cervical SCC.

Intracoronary infusion of Wharton's jelly-derived mesenchymal stem cells in acute myocardial infarction: double-blind, randomized controlled trial.

BACKGROUND: The use of adult stem cells is limited by the quality and quantity of host stem cells. It has been demonstrated that Wharton's jelly-derived mesenchymal stem cells (WJMSCs), a primitive stromal population, could integrate into ischemic cardiac tissues and significantly improve heart function. In this randomized, controlled trial, our aim was to assess the safety and efficacy of intracoronary WJMSCs in patients with ST-elevation acute myocardial infarction (AMI). METHODS: In a multicenter trial, 116 patients with acute ST-elevation MI were randomly assigned to receive an intracoronary infusion of WJMSCs or placebo into the infarct artery at five to seven days after successful reperfusion therapy. The primary endpoint of safety: the incidence of adverse events (AEs) within 18 months, was monitored and quantified. The endpoint of efficacy: the absolute changes in myocardial viability and perfusion of the infarcted region from baseline to four months, global left ventricular ejection fraction (LVEF) from baseline to 18 months were measured using F-18-fluorodeoxyglucose positron emission computed tomography (F-18-FDG-PET) and 99mTc-sestamibi single-photon emission computed tomography (99mTc-SPECT), and two-dimensional echocardiography, respectively. RESULTS: During 18 months follow-up, AEs rates and laboratory tests including tumor, immune, and hematologic indexes were not different between the two groups. The absolute increase in the myocardial viability (PET) and perfusion within the infarcted territory (SPECT) was significantly greater in the WJMSC group [6.9 ± 0.6 % (95 %CI, 5.7 to 8.2)] and [7.1 ± 0.8 % (95 %CI, 5.4 to 8.8) than in the placebo group [3.3 ± 0.7 % (95 %CI, 1.8 to 4.7), P <0.0001] and 3.9 ± 0.6(95 %CI, 2.8 to 5.0), P = 0.002] at four months. The absolute increase in the LVEF at 18 months in the WJMSC group was significantly greater than that in the placebo group [7.8 ± 0.9 (6.0 to approximately 9.7) vs. 2.8 ± 1.2 (0.4 to approximately 5.1), P = 0.001]. Concomitantly, the absolute decreases in LV end-systolic volumes and end-diastolic volumes at 18 months in the WJMSC group were significantly greater than those in the placebo group (P = 0.0004, P = 0.004, respectively). CONCLUSIONS: Intracoronary infusion of WJMSCs is safe and effective in patients with AMI, providing clinically relevant therapy within a favorable time window. This study encourages additional clinical trials to determine whether WJMSCs may serve as a novel alternative to BMSCs for cardiac stem cell-based therapy. TRIAL REGISTRATION: Clinical Trials NCT01291329 (02/05/2011).

NADPH oxidase contributes to the left ventricular dysfunction induced by sinoaortic denervation in rats.

The aim of this work was to investigate the role nicotinamide adenine dinucleotide phosphate (NADPH) oxidase on left ventricular dysfunction of rats submitted to sinoaortic denervation (SAD). Experiment 1: 8 weeks after SAD of rats, NADPH oxidase in left ventricles was assayed by Western blotting analysis. Experiment 2: Rats were subjected to SAD and received treatment with apocynin (an NADPH oxidase inhibitor, 30 mg/kg/day, intragastric administration) for 8 weeks; 8 weeks after SAD, Nox2 and Nox4 expressions and Rac1 activity of left ventricles were higher in SAD rats than those in sham-operated rats. Although treatment of SAD rats with apocynin did not affect blood pressure, blood pressure variability (BPV), and baroreflex function, it significantly attenuated left ventricular hypertrophy marked by reduced expression of atrial natriuretic factor and ß-myosin heavy chain. Treatment of SAD rats with apocynin abated oxidative stress marked by reduced malondialdehyde formation and suppressed nuclear factor-kappa B (NFκB) activation; inflammation marked by reduced monocyte chemoattractant protein-1 expression and myeloperoxidase activity; attenuated endoplasmic reticulum stress marked by reduced expression of CCAAT-enhancer-binding protein homologous protein, chaperone-glucose-regulated protein 78, and X-box protein 1; and alleviated cardiac fibrosis marked by reduced mRNA levels of collagens I and III and transforming growth factor beta. In conclusion, exaggerated BPV induces chronic myocardial oxidative stress and thereby aggravates cardiac remodeling in rats. These data suggest a potential role of NADPH oxidases in the pathogenesis of cardiac dysfunction induced by exaggerated BPV.

miR146a impairs the IFN-induced anti-HBV immune response by downregulating STAT1 in hepatocytes.

BACKGROUND & AIMS: Previous studies have shown that hepatitis B virus (HBV) interferes with host antiviral immunity via multiple pathways. In clinical practice, interferon resistance is a serious issue for treatment of HBV infection. Now, miRNAs have been reported to be widely involved in antiviral immunity and have become a novel tool to study virus-host interaction. We question whether miRNAs play a role in HBV-induced interferon resistance in hepatocytes. METHODS: MiRNAs levels in HepG2 and HepG2.2.15 cells were compared by qRT-PCR. The effects of miR146a on HBV infection were characterized by interference miR146a level, followed by the quantification of HBV mRNA, DNA and antigens. We employed qRT-PCR and western blot to study the effects of miR146a on the IFN-α signalling pathway. The miR146a promoter activity was validated by a luciferase reporter assay. RESULTS: HBV infection impaired IFN-α signalling pathway in hepatocytes. MiR146a was upregulated in HBV+ HepG2.2.15 cells, and the transcriptional activity of miR146a in HepG2.2.15 cells was increased compared with HepG2 cells. HBV infection, especially the introduction of HBx, induced miR146a expression in vitro. Moreover, miR146a attenuated the production of type I interferon-induced antiviral factors. Low STAT1 levels were noticed in HBV+ HCC cells, and the luciferase reporter assay showed that STAT1 was post-transcriptionally downregulated by miR146a. Furthermore, the silencing of miR146a by antisense inhibitors enhanced IFN-α-mediated anti-HBV efficiency. CONCLUSIONS: Our findings demonstrate that HBV infection promotes miR146a transcription, which represses STAT1 and results in interferon resistance. These observations reveal a novel role for miR146a in HBV immunopathogenesis, and provide a potential target for the therapeutic recovery of IFN-α-induced anti-HBV effects.

A critical challenge: dosage-related efficacy and acute complication intracoronary injection of autologous bone marrow mesenchymal stem cells in acute myocardial infarction.

BACKGROUND: Previous studies showed improvement in heart function by injecting bone marrow mesenchymal stem cells (BMSCs) after AMI. Emerging evidence suggested that both the number and function of BMSCs decline with ageing. We designed a randomized, controlled trial to further investigate the safety and efficacy of this treatment. METHODS: Patients with ST-elevation AMI undergoing successful reperfusion treatment within 12 hours were randomly assigned to receive an intracoronary infusion of BMSCs (n=21) or standard medical treatment (n=22) (the numbers of patients were limited because of the complication of coronary artery obstruction). RESULTS: There is a closely positive correlation of the number and function of BMSCs vs. the cardiac function reflected by LVEF at baseline (r=0.679, P=0.001) and at 12-month follow-up (r=0.477, P=0.039). Six months after cell administration, myocardial viability within the infarct area by 18-FDG SPECT was improved in both groups compared with baseline, but no significant difference in the BMSCs compared with control groups (4.0±0.4% 95%CI 3.1-4.9 vs. 3.2±0.5% 95%CI 2.1-4.3, P=0.237). 99mTc-sestamibi SPECT demonstrated that myocardial perfusion within the infarct area in the BMSCs did not differ from the control group (4.4±0.5% 95%CI 3.2-5.5 vs. 3.9±0.6% 95%CI 2.6-5.2, P=0.594). Similarly, LVEF after 12 and 24 months follow-up did not show any difference between the two groups. In the BMSCs group, one patient suffered a serious complication of coronary artery occlusion during the BMSCs injection procedure. CONCLUSIONS: The clinical benefits of intracoronary injection of autologous BMSCs in acute STEMI patients need further investigation and reevaluation.

Common expression of stemness molecular markers and early cardiac transcription factors in human Wharton's jelly-derived mesenchymal stem cells and embryonic stem cells.

At present, there are still significant barriers that impede the clinical use of hESCs and iPS cells, including ethics, immunorejection, tumorigenesis from hESCs, and teratoma formation from iPS cells. It is therefore necessary to search for alternative sources of stem cells. WJ-MSCs originate from embryonic epiblasts and possess properties intermediate between hESCs and adult stem cells. However, the stemness properties of molecules in WJ-MSCs remain unclear compared to those of hESCs. In the present study, we isolated WJ-MSCs by a nonenzymatic method. Further, using microarray analysis by Affymetrix GeneChip and functional network analyses, we determined the degree of expression of stemness genes exhibited by the Human Stem Cell Pluripotency array. We also defined a wide range of stem cell gene expression in the WJ-MSCs in comparison with hESCs. At the same time, the definitive markers of early cardiac precursor cells and more committed progenitors were further characterized in WJ-MSCs. Our results demonstrated for the first time that WJ-MSCs had significant expression of undifferentiated human embryonic stem cell core markers, such as SOX2, NANOG, LIN28, SSEA1, SSEA3, SSEA4, KLF4, c-MYC, CRIPTO, and REX1, with a relatively lower level of expression than in hESCs. We also found WJ-MSCs have high expression of early cardiac transcription factors, such as Flk-1, Isl-1, and Nkx2.5. Functional analysis revealed signature genes of WJ-MSCs with specific roles involved in immune, cytoskeletal, and chemokine regulation, cell adhesion, and cell signaling. Our study indicated that there is a significant overlap between the stemness genes expressed by hESCs and WJ-MSCs. WJ-MSCs harbor a true stem cell population and are promising cells for stem cell-based therapies.

Cytotoxic constituents of Viscum coloratum.

Phytochemical studies on Viscum coloratum have resulted in the isolation of nineteen compounds. The structures of the isolated compounds were identified on the basis of 1D, 2D NMR and HR-ESI-Q-TOF-MS. Pachypodol (4) and ombuine (6) were characterized in the family Loranthaceae for the first time. 1,7-Bis(4-hydroxyphenyl)-1,4-heptadien-3-one (8) and 5-hydroxy-3,7,3'-trimethoxyflavone-4'-O-beta-D-glucoside (13) were two new natural compounds, which exhibited cytotoxic activities against four human tumour cell lines (HeLa, SGC-7901, MCF-7, and U251).

Vibro-acoustic analysis of a rectangular cavity bounded by a flexible panel with elastically restrained edges.

A coupled system consisting of an acoustic cavity and an elastic panel is a classical problem in structural acoustics and is typically analyzed using modal approaches based on in vacuo structural modes and the rigidly walled acoustic modes which are pre-determined based on separate component models. Such modeling techniques, however, tend to suffer the following drawbacks or limitations: (a) a panel is only subjected to ideal boundary conditions such as the simply supported, (b) the coupling between the cavity and panel is considered weak, and (c) the particle velocity cannot be correctly predicted from the pressure gradient on the contacting interface, to name a few. Motivated by removing these restrictions, this paper presents a general method for the vibro-acoustic analysis of a three-dimensional (3D) acoustic cavity bounded by a flexible panel with general elastically restrained boundary conditions. The displacement of the plate and the sound pressure in the cavity are constructed in the forms of standard two-dimensional and 3D Fourier cosine series supplemented by several terms introduced to ensure and accelerate the convergence of the series expansions. The unknown expansions coefficients are treated as the generalized coordinates and determined using the Rayleigh-Ritz procedure based on the energy expressions for the coupled structural acoustic system. The accuracy and effectiveness of the proposed method are demonstrated through numerical examples and comparisons with the results available in the literature.

Comparison of the effect of various disaccharides on frozen goat spermatozoa.

In order to create a bank of goat spermatozoa, it was important to evaluate the protective effect of five different cryoprotectant extenders. Additionally, this study determined whether the cryoprotective effect of trehalose is superior to that of other disaccharides. The data indicate that the motility (~20%) and path velocity (~15 µm/s) of spermatozoa frozen with extenders containing disaccharide were significantly less than that of spermatozoa frozen with extender containing no disaccharide (45.21 ± 3.51% and 28.66 ± 13.57 µm/s, respectively; p<0.01). Moreover, in the presence of disaccharide, the percentage of goat spermatozoa with exposed phosphatidylserine following cryopreservation was over 35% and significantly higher than spermatozoa frozen in the absence of disaccharide (4.88 ± 3.41%, p<0.01). In addition, the presence of disaccharide did not increase the thermal resistance or protect membrane integrity of frozen spermatozoa. However, the percentage of cells with an intact acrosome following cryopreservation in the presence of disaccharide was significantly greater than that of cells frozen with no disaccharide (p<0.05). Finally, the protective effect of trehalose on frozen goat spermatozoa was similar to that of sucrose, maltose, or lactose (p>0.05). In conclusion, the effect of trehalose on frozen goat spermatozoa is not superior to that of other disaccharides including sucrose, maltose, or lactose. Moreover, disaccharide used as the main solute does not improve the quality of frozen goat spermatozoa except for protection of acrosome integrity. The role of disaccharide on frozen goat spermatozoa still needs further elucidation.

Acoustic analysis of a rectangular cavity with general impedance boundary conditions.

A Fourier series method is proposed for the acoustic analysis of a rectangular cavity with impedance boundary conditions arbitrarily specified on any of the walls. The sound pressure is expressed as the combination of a three-dimensional Fourier cosine series and six supplementary two-dimensional expansions introduced to ensure (accelerate) the uniform and absolute convergence (rate) of the series representation in the cavity including the boundary surfaces. The expansion coefficients are determined using the Rayleigh-Ritz method. Since the pressure field is constructed adequately smooth throughout the entire solution domain, the Rayleigh-Ritz solution is mathematically equivalent to what is obtained from a strong formulation based on directly solving the governing equations and the boundary conditions. To unify the treatments of arbitrary nonuniform impedance boundary conditions, the impedance distribution function on each specified surface is invariantly expressed as a double Fourier series expansion so that all the relevant integrals can be calculated analytically. The modal parameters for the acoustic cavity can be simultaneously obtained from solving a standard matrix eigenvalue problem instead of iteratively solving a nonlinear transcendental equation as in the existing methods. Several numerical examples are presented to demonstrate the effectiveness and reliability of the current method for various impedance boundary conditions, including nonuniform impedance distributions.

High-throughput parallel reactor system for propylene oxidation catalyst investigation.

A high-throughput reactor system was designed for catalyst testing, which includes two important sections: the gas flow splitters and the parallel reactor. Each gas flow splitter could split one gas stream to 64 streams (8 x 8). The current system has two gas splitters that could feed two kinds of gases (from mass flow controllers) to a 64-channel (8 x 8) parallel fixed-bed reactor. The reactor is composed of tube connectors, a reactor tube array, a heating block, a product collector, and a temperature controller. The reactor system could test 64 catalysts simultaneously and give results, which are comparable with a regular single-channel microreactor. For the purpose of verifying the validity of the reactor system, propylene oxidation to prepare acrolein was used as the probing reaction. In order to analyze the reaction products, a high-throughput colorimetric diffusion-reflection imaging method was developed for the analysis of acrolein. By comparing the results from colorimetric diffusion-reflection imaging analysis with that from the traditional gas chromatography spectrometer with thermal conductivity detectors, a colorimetric diffusion-reflection imaging method was confirmed to be reliable and accurate in acrolein analysis.