The cause of seasonal failure of a nitrifying municipal landfill leachate treatment plant utilizing a fixed biofilm was investigated by wastewater analyses and batch respirometric tests at every ...treatment stage. Nitrification of the leachate treatment plant was severely affected by the seasonal temperature variation. High free ammonia (NH
3-N) inhibited not only nitrite oxidizing bacteria (NOB) but also ammonia oxidizing bacteria (AOB). In addition, high pH also increased free ammonia concentration to inhibit nitrifying activity especially when the NH
4-N level was high. The effects of temperature and free ammonia of landfill leachate on nitrification and nitrite accumulation were investigated with a semi-pilot scale biofilm airlift reactor. Nitrification rate of landfill leachate increased with temperature when free ammonia in the reactor was below the inhibition level for nitrifiers. Leachate was completely nitrified up to a load of 1.5
kg NH
4-N m
−3
d
−1 at 28
°C. The activity of NOB was inhibited by NH
3-N resulting in accumulation of nitrite. NOB activity decreased more than 50% at 0.7
mg NH
3-N L
−1. Fluorescence in situ hybridization (FISH) was carried out to analyze the population of AOB and NOB in the nitrite accumulating nitrifying biofilm. NOB were located close to AOB by forming small clusters. A significant fraction of AOB identified by probe Nso1225 specifically also hybridized with the
Nitrosomonas specific probe Nsm156. The main NOB were
Nitrobacter and
Nitrospira which were present in almost equal amounts in the biofilm as identified by simultaneous hybridization with
Nitrobacter specific probe Nit3 and
Nitrospira specific probe Ntspa662.
For the reasonable comparison of chemical and enzymatic polymerization, manganese(III) acetate and manganese peroxidase (MnP)-catalyzed synthesis of polystyrenes were chosen and studied with respect ...to the yield and the polydispersity of polymer particles. MnP allowed the production of polystyrene in a higher yield and higher polydispersity (82.34% and 2.61) than manganese(III) acetate (77.90% and 1.75). This is believed to be due to a gradual supply of initiator radicals via a catalytic cycle in MnP-catalyzed polymerization, whereas radicals are generated all at once in Mn(III)-mediated polymerization. NMR spectroscopy revealed that atactic polystyrene was produced by emulsion polymerization using Mn(III) or MnP.
The purpose of this research is to find out the effects of free ammonia concentration and dissolved oxygen on nitrification and nitrite accumulation in a biofilm airlift reactor. Free ammonia ...seriously inhibited the activity of nitrite oxidizers at the concentration higher than 0.1 mg NH3-N/L and it was very effective for nitrite accumulation. Dissolved oxygen limitation in the biofilm also caused nitrite accumulation. Long term inhibition decreased the growth rate for nitrite oxidizers, and ammonia oxidizers were the dominant nitrifiers in the wastewater nitrification. Selective accumulation of ammonia oxidizers in the biofilm could be another reason for nitrite accumulation. Free ammonia inhibited nitrite oxidizers immediately, and adaptation to free ammonia was not observed. Therefore, the optimum control of free ammonia and dissolved oxygen concentration is critical for nitrite accumulation and the strategy can be used for selective accumulation of ammonia oxidizers in a bioreactor system.
Free ammonia ($NH_3$-N) inhibition of nitrite-oxidizing bacteria (NOB) has been widely studied for partial nitrification (or nitrite accumulation) and denitrification via nitrite ($NO_2^-$-N) as a ...low-cost treatment of ammonium containing wastewater. The literature on $NH_3$-N inhibition of NOB, however, shows disagreement about the threshold $NH_3$-N concentration and its degree of inhibition. In order to clarify the confusion, a simple and cheap respirometric method was devised to investigate the effect of free ammonia inhibition of NOB. Sludge samples from an autotrophic nitrifying reactor were exposed to various $NH_3$-N concentrations to measure the maximum specific nitrite oxidation rate ($\hat{K}_{NO}$) using a respirometer. NOB biomass was estimated from the yield values in the literature. Free ammonia inhibition of nitrite oxidizing bacteria was reversible and the specific nitrite oxidation rate ($K_{NO}$) decreased from 0.141 to 0.116, 0.100, 0.097 and 0.081 mg $NO_2^-$-N/mg NOB h, respectively, as the $NH_3$-N concentration increased from 0.0 to 1.0, 4.1, 9.7 and 22.9 mg/L. A nonlinear regression based on the noncompetitive inhibition mode gave an estimate of the Inhibition concentration ($K_I$) of free ammonia to be 21.3 mg $NH_3$-N/L. Previous studies gave $\hat{K}_{NO}$ of Nitrobacter and Nitrospira as 0.120 and 0.032 mg/mg VSS h. The free ammonia concentration which inhibits Nitrobacter was $30{\sim}50\;mg$ $NH_3$-N/L and Nitrospira was inhibited at $0.04{\sim}0.08\;mg$ $NH_3$-N/L. The results support the fact that Nitrobacter is the dominant NOB in the reactor. The variations in the reported values of free ammonia inhibition may be due to the different species of nitrite oxidizers present in the reactors. The respirometric method provides rapid and reliable analysis of the behavior and community of the nitrite oxidizing bacteria.
Summary
Inhibitor of apoptosis proteins (IAPs) are overexpressed in the majority of cancers and prevent apoptosis by inhibiting caspases. IAPs have therefore attracted considerable attention as ...potential targets for anticancer therapy. Here, we demonstrated that HM90822 (abbreviated HM822; a new synthetic IAP antagonist) induced apoptotic cell death via proteasome-dependent degradation of BIR2/3 domain-containing IAPs in human pancreatic cancer cells. HM822 inhibited the expression of XIAP and cIAP1/2 proteins in Panc-1 and BxPC-3 cells, which are sensitive to HM822. HM822 also induced IAP ubiquitination and promoted proteasome-dependent IAP degradation. However, cells expressing phospho-XIAP (Ser87) and AKT exhibited resistance to HM822. In other words, the overexpression of AKT-CA (constitutive active form for AKT) or AKT-WT induced resistance to HM822. In addition, in Panc-1 xenograft and orthotopic mouse models, we revealed that tumor growth was suppressed by the administration of HM822. Taken together, these results suggest that HM822 induces apoptosis through ubiquitin/proteasome-dependent degradation of BIR3 domain-containing IAPs. These findings suggest that phospho-XIAP and phospho-AKT may be used as biomarkers for predicting the efficacy of HM822 in pancreatic cancer patients.
Recently, several studies suggested that radiofrequency (RF) ablation of the genicular nerves is a safe and effective therapeutic procedure for intractable pain associated with chronic knee ...osteoarthritis (OA). Diagnostic genicular nerve block (GNB) with local anesthetic has been generally conducted before making decisions regarding RF ablation. Although GNB has been recently performed together with corticosteroid, the analgesic effects of corticosteroids for treating chronic pain remain controversial.
The current study aims to assess the effects of combining corticosteroids and local anesthesia during ultrasound-guided GNB in patients with chronic knee OA.
A randomized, double-blinded institutional study.
This study took place at Asan Medical Center in Seoul, Korea.
Forty-eight patients with chronic knee OA were randomly assigned to either the lidocaine alone group (n = 24) or lidocaine plus triamcinolone (TA) group (n = 24) before ultrasound-guided GNB. Visual analog scale (VAS), Oxford Knee Score (OKS), and global perceived effects (7-point scale) were assessed at baseline and at 1, 2, 4, and 8 weeks after the procedure.
The VAS scores were significantly lower in the lidocaine plus TA group than in the lidocaine alone group at both 2 (P < 0.001) and 4 (P < 0.001) weeks after GNB. The alleviation of intense pain in the lidocaine plus TA group was sustained up to 2 weeks after the procedure, in accordance with the definition of a minimal clinically important improvement. Although a similar intergroup difference in OKSs was observed at 4 weeks (P < 0.001), the clinical improvement in functional capacity lasted for only one week after the reassessment of OKSs, in accordance with a minimal important change. No patient reported any postprocedural adverse events during the follow-up period.
The emotional state of the patients, which might affect the perception of knee pain, was not evaluated. The follow-up period was 2 months; this period might be insufficient to validate the short-term effects of GNB.
Ultrasound-guided GNB, when combined with a local anesthetic and corticosteroid, can provide short-term pain relief. However, the clinical benefit of corticosteroid administration was not clear in comparison with local anesthesia alone. Given the potential adverse effects, corticosteroids might not be appropriate as adjuvants during a GNB for chronic knee OA.The study protocol was approved by our institutional review board (2012-0210), and written informed consent was obtained from all patients. The trial was registered with the Clinical Research Information Service (KCT 0001139).
Chronic pain, knee osteoarthritis, genicular nerve block, ultrasound, corticosteroid, local anesthetic, visual analog scale, Oxford Knee Score.
Recent functional genomic studies revealed that the oncogenic activity of focally amplified lncRNA on chromosome 1 (FAL1, ENSG00000228126) contributes to tumor growth by p21 repression in human ...cancers. However, the expression of FAL1 was not investigated in papillary thyroid cancer (PTC). We aimed to determine if FAL1 was up-regulated in PTC compared to paired contralateral normal thyroid tissues, and to investigate the potential targets of this lncRNA and its clinicopathological significance in PTC. We analyzed FAL1 and p21 expression levels in 100 PTC samples and matched normal thyroid tissue by qRT-PCR. Using lncRNA microarray data from the Gene Expression Omnibus (accession no. GSE61763), we explored potential targets of FAL1 by Gene Set Enrichment Analysis, followed by verification by qRT-PCR in our PTC samples. A cross-sectional observational study was conducted to investigate the relationship between patients' clinicopathological features and FAL1 expression. FAL1 expression was significantly higher in PTC than in paired normal thyroid tissues (paired t test, P < 0.001). p21 mRNA expression was also increased, not decreased, in PTC, and had no correlation with FAL1 expression (r = 0.0897, P = 0.4002). Gene Set Enrichment Analysis, using publicly available microarray data, indicated that a gene set related to the cell cycle, including E2F transcription factors 1 and 2, and cyclin D1, was coordinately enriched among samples with high FAL1 expression. A volcano plot showed that E2F1, E2F2, and VEGFA mRNAs were increased in the high FAL1 samples. In clinicopathological analyses, multifocality was more frequently observed in PTC patients with high FAL1 (P = 0.018). Multivariate analysis showed that high FAL1 expression increased the risk of multifocality (after adjustment for clinical variables, OR = 4.019, CI = 1.041-11.020, P = 0.043). FAL1 may have a role in cell-cycle progression and may be associated with aggressive tumor behavior in PTC.
This study was performed to examine the usefulness of subscores on the Mini-Mental State Examination (MMSE) for predicting the progression of Alzheimer's disease (AD) dementia in individuals with ...mild cognitive impairment (MCI).
A total of 306 MCI individuals in the Alzheimer's Disease Neuroimaging Initiative database were included in the study. Standardized clinical and neuropsychological tests were performed at baseline and at 2-year follow-up. Logistic regression analysis was conducted to examine the MMSE total and subscale scores to predict progression to AD dementia in MCI individuals.
The MMSE total score and the MMSE memory, orientation, and construction subscores were inversely associated with AD progression after controlling for all potential confounders; MMSE attention and language subscores were not correlated with AD progression. The MMSE delayed recall score among the MMSE memory subscores and the MMSE time score among the orientation subscores, especially week and day, were inversely associated with AD progression; the MMSE immediate recall and place scores were not correlated with progression.
Our findings suggest that the MMSE memory, orientation, and construction subscores, which are simple and readily available clinical measures, could provide useful information to predict AD dementia progression in MCI individuals in practical clinical settings.
A new method for accurately estimating the interface bonding strength of clad metals, which is not easy to determine from load–displacement curves or optical micrographs, using digital image ...correlation during tensile tests is proposed. As an example, the interface bonding strain and stress of a three-layered clad specimen produced by high-pressure torsion were determined at the point where the interface normal strain starts to increase. This method shed light on the development of complicatedly layered and composite materials as well as of clad metals, for which interface bonding strengths are critical.
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