Variations in antibiotic resistance genes and microbial community in sludges passing through biological nutrient removal and anaerobic digestion processes in municipal wastewater treatment plants.

Antimicrobial resistance (AMR) represents a relentless, silent pandemic. Contributing to this are wastewater treatment plants (WWTPs), a potential source of antibiotic resistance genes' (ARGs) transmission to the environment, threatening public health. The presence of ARGs in pathogenic bacteria and their release into the environment by WWTPs threatens the public health. The current study investigated changes in ARGs' abundance in biological nutrient removal (BNR) processes and anaerobic digestion (AD) reactors of two WWTPs. Also, microbial community structure, which is known to shape the distribution and abundance of ARGs, was also analyzed. The relative abundance of eight ARGs (tetX, tetA, tetM, TEM, sul1, sul2, ermB and qnrD) was quantified as ARGs' copies/16 S rRNA gene copies using quantitative polymerase chain reaction (qPCR). Microbial community composition was assessed by 16 S rRNA microbiome sequencing analysis. TetX was prevalent among the eight ARGs, followed by TEM and sul1. However, its abundance was decreased in the AD sludges compared to BNR sludges. Proteobacteria was the major bacterial phylum found in all the sludge samples, while Arcobacter, 12up and Acidovorax were the predominant genera. Acinetobacter and Flavobacterium were significantly more abundant in the BNR sludges, while 12up and Aeromonas were predominant in AD sludges. Principal component analysis (PCA) revealed a clear difference in dominant ARGs and bacteria between the sludges in the processes of BNR and AD of the two WWTPs. Clinically relevant bacterial genera, Klebsiella and Enterococcus, found in both the BNR and AD sludges, were significantly correlated with the tetX gene. Throughout this study, the relationship between microbial communities and specific ARGs was revealed, illustrating that the composition of the microbial community could play a vital role in the abundance of ARGs. These results will better inform future studies aimed at controlling the spread of ARGs and their potential hosts from WWTPs.

Bioactivities of Phenolic Compounds from Kiwifruit and Persimmon.

Fruit used in the common human diet in general, and kiwifruit and persimmon particularly, displays health properties in the prevention of heart disease. This study describes a combination of bioactivity, multivariate data analyses and fluorescence measurements for the differentiating of kiwifruit and persimmon, their quenching and antioxidant properties. The metabolic differences are shown, as well in the results of bioactivities and antioxidant capacities determined by ABTS, FRAP, CUPRAC and DPPH assays. To complement the bioactivity of these fruits, the quenching properties between extracted polyphenols and human serum proteins were determined by 3D-fluorescence spectroscopy studies. These properties of the extracted polyphenols in interaction with the main serum proteins in the human metabolism (human serum albumin (HSA), α-ß-globulin (α-ß G) and fibrinogen (Fgn)), showed that kiwifruit was more reactive than persimmon. There was a direct correlation between the quenching properties of the polyphenols of the investigated fruits with serum human proteins, their relative quantification and bioactivity. The results of metabolites and fluorescence quenching show that these fruits possess multiple properties that have a great potential to be used in industry with emphasis on the formulation of functional foods and in the pharmaceutical industry. Based on the quenching properties of human serum proteins with polyphenols and recent reports in vivo on human studies, we hypothesize that HSA, α-ß G and Fgn will be predictors of coronary artery disease (CAD).

Genetic and metabolic links between the murine microbiome and memory.

BACKGROUND: Recent evidence has linked the gut microbiome to host behavior via the gut-brain axis [1-3]; however, the underlying mechanisms remain unexplored. Here, we determined the links between host genetics, the gut microbiome and memory using the genetically defined Collaborative Cross (CC) mouse cohort, complemented with microbiome and metabolomic analyses in conventional and germ-free (GF) mice. RESULTS: A genome-wide association analysis (GWAS) identified 715 of 76,080 single-nucleotide polymorphisms (SNPs) that were significantly associated with short-term memory using the passive avoidance model. The identified SNPs were enriched in genes known to be involved in learning and memory functions. By 16S rRNA gene sequencing of the gut microbial community in the same CC cohort, we identified specific microorganisms that were significantly correlated with longer latencies in our retention test, including a positive correlation with Lactobacillus. Inoculation of GF mice with individual species of Lactobacillus (L. reuteri F275, L. plantarum BDGP2 or L. brevis BDGP6) resulted in significantly improved memory compared to uninoculated or E. coli DH10B inoculated controls. Untargeted metabolomics analysis revealed significantly higher levels of several metabolites, including lactate, in the stools of Lactobacillus-colonized mice, when compared to GF control mice. Moreover, we demonstrate that dietary lactate treatment alone boosted memory in conventional mice. Mechanistically, we show that both inoculation with Lactobacillus or lactate treatment significantly increased the levels of the neurotransmitter, gamma-aminobutyric acid (GABA), in the hippocampus of the mice. CONCLUSION: Together, this study provides new evidence for a link between Lactobacillus and memory and our results open possible new avenues for treating memory impairment disorders using specific gut microbial inoculants and/or metabolites. Video Abstract.

Colonies of the fungus Aspergillus niger are highly differentiated to adapt to local carbon source variation.

Saprobic fungi, such as Aspergillus niger, grow as colonies consisting of a network of branching and fusing hyphae that are often considered to be relatively uniform entities in which nutrients can freely move through the hyphae. In nature, different parts of a colony are often exposed to different nutrients. We have investigated, using a multi-omics approach, adaptation of A. niger colonies to spatially separated and compositionally different plant biomass substrates. This demonstrated a high level of intra-colony differentiation, which closely matched the locally available substrate. The part of the colony exposed to pectin-rich sugar beet pulp and to xylan-rich wheat bran showed high pectinolytic and high xylanolytic transcript and protein levels respectively. This study therefore exemplifies the high ability of fungal colonies to differentiate and adapt to local conditions, ensuring efficient use of the available nutrients, rather than maintaining a uniform physiology throughout the colony.

Potential utility of graphene-based nano spinel ferrites as adsorbent and photocatalyst for removing organic/inorganic contaminants from aqueous solutions: A mini review.

Toxic substances such as heavy metals or persistent organic pollutants raise global environmental concerns. Thus, diverse water decontamination approaches using nano-adsorbents and/or photocatalysts based on nanotechnology are being developed. Particularly, many studies have examined the removal of organic and inorganic contaminants with novel graphene-based nano spinel ferrites (GNSFs) as potential cost-effective alternatives to traditionally used materials, owing to their enhanced physical and chemical properties. The introduction of magnetic spinel ferrites into 2-D graphene-family nanomaterials to form GNSFs brings various benefits such as inhibited particle agglomeration, enhanced active surface area, and easier magnetic separation for reuse, making the GNSFs highly efficient and eco-friendly materials. Here, we present a short review on the state-of-the-art progresses on developments of GNSFs, as well as their potential application for removing several recalcitrant contaminants including organic dyes, antibiotics, and heavy metal ions. Particularly, the mechanisms involved in the adsorptive and photocatalytic degradation are thoroughly reviewed, and the reusability of the GNSFs is also highlighted. This review concludes that the GNSFs hold great potential in remediating contaminated aquatic environments. Further studies are needed for their practical and large-scale applications.

Protective Effect of Ginseng on Salivary Dysfunction Following Radioiodine Therapy in a Mouse Model.

BACKGROUND: Following radioiodine (RI) therapy, oxidative stress is a putative damage mechanism resulting in salivary gland (SG) dysfunction. Since ginseng is a known anti-oxidative herb, we examined the SG radioprotective effects of Korea red ginseng (KRG) in a mouse model, when administered prior to RI. METHODS: Four-week-old mice (n = 60) were divided into four groups: (1) normal control, (2) RI only treated (0.01 mCi/g, orally), (3) KRG administered (0.2 mg/g, intraperitoneal injection) 0.5 and 24 hours before RI, and (4) amifostine-treated group (0.2 mg/g, intraperitoneally) 0.5 hour before RI. The salivary lag times and flow rates were assessed, and sampled tissues were subjected to histologic examinations including hematoxylin and eosin and immunohistochemical staining. Apoptosis was examined by the terminal deoxynucleotidyl transferase biotin-dUDP nick end labeling (TUNEL) assay, and excretion changes in salivary 99mTc pertechnetate were evaluated by single-photon emission computed tomography. RESULTS: The body weight of the KRG group was similar to the control group. Salivary lag times and flow rates in the RI + KRG group were faster than in the RI only group. There was no significant intergroup difference in the SG weight. The RI + KRG group exhibited more mucin-containing parenchyma and less fibrotic tissues than the RI only group. Salivary epithelial (aquaporin 5) and myoepithelial (smooth muscle actin) cells of the RI + KRG group were protected from radiation damage. Low 8-OhdG (oxidative stress biomarker) and high superoxide dismutase 2 (reactive oxygen species scavenger) immunostaining reactivity was detected in the RI + KRG group when compared with the RI only group. Fewer apoptotic cells were observed in the RI + KRG or amifostine group compared to the RI only group in the TUNEL assay. The 99mTc pertechnetate excretion level recovered in the KRG group. CONCLUSION: Pretreatment with KRG before RI therapy is potentially beneficial in protecting against RI-induced salivary dysfunction.

1H NMR and antioxidant profiles of polar and non-polar extracts of persimmon (Diospyros kaki L.) - Metabolomics study based on cultivars and origins.

Persimmon (Diospyros kaki L.) is one of the most important fruits that has been consumed for its medicinal properties due to the presence of some active metabolites, particularly polyphenols and carotenoids. Previously described methods, including HPLC, were limited in the determination of metabolites in different persimmon varieties. The present study shows the evaluation and the differences among persimmon polar and non-polar extracts by 1H NMR-based metabolomics approach. The hierarchical clustering analysis (HCA) based on score values of principal component analysis (PCA) model was used to analyze the important compounds in investigated fruits. The 1H NMR spectrum of persimmon chloroform (CDCl3) extracts showed different types of compounds as compared to polar methanol-water (CD3OD-D2O) ones. Persimmons growing in Israel were clustered different from those growing in Korea with the abundance of phenolic compounds (gallic, caffeic and protocathecuic acids), carotenoids (ß-cryptoxanthin, lutein, and zeaxanthin), amino acids (alanine), maltose, uridine, and fatty acids (myristic and palmitoleic acids). Glucose, choline and formic acid were more prominent in persimmon growing in Korea. In CD3OD-D2O and CDCl3 persimmon extracts, 43 metabolites were identified. The metabolic differences were shown as well on the results of bioactivities and antioxidant capacities determined by ABTS, FRAP, CUPRAC and DPPH assays. The presented methods can be widely used for quantitation of multiple compounds in many plant and biological samples especially in vegetables and fruits.

Prevention of tracheal inflammation and fibrosis using nitinol stent coated with doxycycline.

OBJECTIVES: This study was conducted to determine whether a nitinol stent coated with doxycycline prevents tracheal inflammation and fibrosis in a rabbit. METHODS: A nitinol stent coated with doxycycline was designed by us. Twelve rabbits were divided into three groups: normal, control (nondoxycycline-coated stent), and doxycycline-coated stent group. The stents were inserted into the tracheal lumen through the oral cavity. Tracheal granulation was evaluated and graded by laryngoscopy. Histological examinations evaluated the inflammatory response and fibrosis. Real-time polymerase chain reaction (PCR) and Western blot assessed the changes to the extracellular matrix (ECM). RESULTS: Endoscopic findings showed that the nitinol stent coated with doxycycline resulted in lesser granulation tissue in the trachea than the noncoated stent. Histologic examination further revealed that the doxycycline-coated stent was associated with decreased inflammatory cells and reduced fibrosis, compared to the noncoated stent. In PCR and Western blot, the doxycycline-coated stent showed lower expression of ECM components inducing fibrosis. CONCLUSION: A nitinol stent coated with doxycycline showed favorable effects in reducing tracheal inflammation and fibrosis in a rabbit model. Further research is required to study the beneficial effects of local application of doxycycline for prevention of tracheal stenosis. LEVEL OF EVIDENCE: NA. Laryngoscope, 128:1558-1563, 2018.

Lipidomics reveals dramatic lipid compositional changes in the maturing postnatal lung.

Lung immaturity is a major cause of morbidity and mortality in premature infants. Understanding the molecular mechanisms driving normal lung development could provide insights on how to ameliorate disrupted development. While transcriptomic and proteomic analyses of normal lung development have been previously reported, characterization of changes in the lipidome is lacking. Lipids play significant roles in the lung, such as dipalmitoylphosphatidylcholine in pulmonary surfactant; however, many of the roles of specific lipid species in normal lung development, as well as in disease states, are not well defined. In this study, we used liquid chromatography-mass spectrometry (LC-MS/MS) to investigate the murine lipidome during normal postnatal lung development. Lipidomics analysis of lungs from post-natal day 7, day 14 and 6-8 week mice (adult) identified 924 unique lipids across 21 lipid subclasses, with dramatic alterations in the lipidome across developmental stages. Our data confirmed previously recognized aspects of post-natal lung development and revealed several insights, including in sphingolipid-mediated apoptosis, inflammation and energy storage/usage. Complementary proteomics, metabolomics and chemical imaging corroborated these observations. This multi-omic view provides a unique resource and deeper insight into normal pulmonary development.

Radioprotective Effect of Epigallocatechin-3-Gallate on Salivary Gland Dysfunction After Radioiodine Ablation in a Murine Model.

OBJECTIVES: Radioiodine (RI) therapy is known to subject cellular components of salivary glands (SG) to oxidative stress leading to SG dysfunction. However, the protective effects of antioxidants on RI-induced SG damage have not been well investigated. The authors investigated the morphometric and functional effects of epigallocatechin-3-gallate (EGCG) administered prior to RI therapy and compared this with the effects of amifostine (a well-known antioxidant) in a murine model of RI sialadenitis. METHODS: Four-week-old female C57BL/6 mice (n=48) were divided into four groups; a normal control group, a RI-treated group (0.01 mCi/g mouse, orally), an EGCG and RI-treated group, and an amifostine and RI-treated group. Animals in these groups were divided into 3 subgroups and euthanized at 15, 30, and 90 days post-RI treatment. Salivary flow rates and lag times were measured, and morphologic and histologic examinations and TUNEL (terminal deoxynucleotidyl transferase biotin-dUDP nick end labeling) assays were performed. Changes in salivary (99m)Tc pertechnetate uptake and excretion were followed by single-photon emission computed tomography. RESULTS: Salivary flow rates and lag times to salivation in the EGCG or amifostine groups were better than in the RI-treated group. Histologic examinations of SGs in the EGCG or amifostine group showed more mucin-rich parenchyma and less periductal fibrosis than in the RI-treated group. Fewer apoptotic cells were observed in acini, ducts, and among endothelial cells in the EGCG or amifostine group than in the RI group. In addition, patterns of (99m)Tc pertechnetate excretion were quite different in the EGCG or amifostine group than in the RI group. CONCLUSION: EGCG supplementation before RI therapy could protect from RI-induced SG damage in a manner comparable to amifostine, and thus, offers a possible means of preventing SG damage by RI.

Nitrification inhibition by hexavalent chromium Cr(VI)--Microbial ecology, gene expression and off-gas emissions.

The goal of this study was to investigate the responses in the physiology, microbial ecology and gene expression of nitrifying bacteria to imposition of and recovery from Cr(VI) loading in a lab-scale nitrification bioreactor. Exposure to Cr(VI) in the reactor strongly inhibited nitrification performance resulting in a parallel decrease in nitrate production and ammonia consumption. Cr(VI) exposure also led to an overall decrease in total bacterial concentrations in the reactor. However, the fraction of ammonia oxidizing bacteria (AOB) decreased to a greater extent than the fraction of nitrite oxidizing bacteria (NOB). In terms of functional gene expression, a rapid decrease in the transcript concentrations of amoA gene coding for ammonia oxidation in AOB was observed in response to the Cr(VI) shock. In contrast, transcript concentrations of the nxrA gene coding for nitrite oxidation in NOB were relatively unchanged compared to Cr(VI) pre-exposure levels. Therefore, Cr(VI) exposure selectively and directly inhibited activity of AOB, which indirectly resulted in substrate (nitrite) limitation to NOB. Significantly, trends in amoA expression preceded performance trends both during imposition of and recovery from inhibition. During recovery from the Cr(VI) shock, the high ammonia concentrations in the bioreactor resulted in an irreversible shift towards AOB populations, which are expected to be more competitive in high ammonia environments. An inadvertent impact during recovery was increased emission of nitrous oxide (N2O) and nitric oxide (NO), consistent with recent findings linking AOB activity and the production of these gases. Therefore, Cr(VI) exposure elicited multiple responses on the microbial ecology, gene expression and both aqueous and gaseous nitrogenous conversion in a nitrification process. A complementary interrogation of these multiple responses facilitated an understanding of both direct and indirect inhibitory impacts on nitrification.

Salivary gland function after sialendoscopy for treatment of chronic radioiodine-induced sialadenitis.

BACKGROUND: The purpose of this study was to determine whether sialendoscopy could ameliorate radioactive iodine-induced obstructive sialadenitis and restore the salivary gland dysfunction in recalcitrant radioactive iodine sialadenitis. METHODS: Ten patients with 15 parotid glands of chronic radioactive iodine sialadenitis who did not respond to medical treatment were enrolled in this prospective study. We assessed subjective symptom scores and evaluated the objective salivary gland functions before and 3 months after sialendoscopy. RESULTS: The post-sialendoscopic obstructive symptoms were significantly improved relative to pre-sialendoscopy (p = .009). Xerostomia-related symptom scores post-sialendoscopy did not differ significantly from the pre-sialendoscopy scores. Stimulated salivary flow rate post-sialendoscopy tended to increase relative to pre-sialendoscopy. No pre-sialendoscopic parameters associated with salivary uptake and secretion by salivary gland scintigraphy were significantly improved post-sialendoscopy. CONCLUSION: These results show that sialendoscopy can improve obstructive symptoms; however, it seems to have some limitations for relief of xerostomia and improvement of salivary gland dysfunctions in recalcitrant chronic radioactive iodine sialadenitis.

Effects of Salivary Secretion Stimulation on the Treatment of Chronic Radioactive Iodine-Induced Sialadenitis.

BACKGROUND: The aim of this prospective study was to investigate the effect of salivary stimulation therapy using pilocarpine (a cholinergic agent) on chronic radioactive iodine (RAI)-induced sialadenitis. METHODS: Sixty-one patients with a diagnosis of chronic RAI-induced sialadenitis after thyroidectomy and RAI therapy were enrolled in this prospective study. Patients received salivary stimulation therapy with pilocarpine (5 mg, 3 times daily) over a 3-month period. Subjective symptom scores were assessed using self-reported questionnaires. Salivary flow rates (SFRs) were measured and salivary gland scintigraphy (SGS) was performed to evaluate objective salivary gland functions. RESULTS: After salivary stimulation therapy, subjective symptom scores were significantly improved (p=0.002), but posttreatment unstimulated and stimulated SFRs did not differ significantly from pretreatment values. SGS parameters, that is, uptake ratio (UR), maximum accumulation (MA), Tmin, and maximum secretion (MS) of parotid and submandibular glands were nonsignificantly different after salivary stimulation therapy. CONCLUSION: The study shows that salivary stimulation therapy may reduce the subjective symptoms of RAI-induced chronic sialadenitis but does not significantly induce functional restoration.

Application of a combined three-stage system for reclamation of tunnel construction wastewater.

A combined three-stage system, (1) coagulation (2) zeocarbon filtration and (3) membrane filtration, a combination of microfiltration (MF) and reverse osmosis (RO), was investigated for reclamation of tunnel construction wastewater having a salinity of 10.8-12.9‰ and a concentration of suspended solids (SS) in the range of 264-1084 mg/L. The initial stages - coagulation, zeocarbon filtration and MF - served as a precursor to RO membrane filtration to successfully reduce water contaminants to less than 0.2 nephelometric turbidity units (NTU) of turbidity, thereby minimizing the potential for fouling. The RO system subsequently removed over 99% of remaining pollutants including ionic substances, resulting in less than 0.02 NTU turbidity, less than 0.04 mg/L total nitrogen (TN) and less than 0.01 mg/L total phosphorus (TP). Also, addition of an RO system markedly reduced high salt concentrations (high chloride (Cl(-)) concentrations) in the wastewater, exceeding 99% salt elimination. Thus, reclaimed water from our combined system met and exceeded currently regulatory quality standards for wastewater reuse (turbidity ≤ 2.0 NTU; TN ≤ 10 mg/L; TP ≤ 0.5 mg/L; Cl(-) ≤ 250 mg/L).

Surface-modified silicone T-tubes for prevention of tracheal stenosis in a rabbit model.

OBJECTIVES/HYPOTHESIS: This study was conducted to determine whether a surface-modified tracheal T-tube can prevent tracheal stenosis in a rabbit model. STUDY DESIGN: Animal model study. METHODS: We designed surface-modified tracheal T-tubes in which silicone rubber was modified by coating it with hyaluronic acid (HA) or polyethylene glycol (PEG). Sixteen rabbits were divided into four insertion groups: normal, silicone tube, silicone tube coated with HA, and silicone tube coated with PEG. Surface-modified tubes were inserted into the tracheal lumen after a scraping injury on the inner tracheal mucosa around the preformed tracheostoma. Laryngoscopy was performed to evaluate formation of stenosis in the trachea. Histological examinations were performed to evaluate epithelial thickness, inflammatory response, and fibrosis. RESULTS: Endoscopic finding showed that the HA- and PEG-coated tube groups had less granulation tissue in the trachea than the noncoated tube group. Greater epithelialization was observed in the noncoated tube group than in the normal group. HA- and PEG-coated tube groups showed a tendency to decreasing epithelialization compared with the noncoated tube group. More inflammatory cells were observed in the noncoated tube group than in the normal group, and fewer inflammatory cells were observed in the HA- and PEG-coated tube groups than in the noncoated tube group. The noncoated tube group showed a greater area of fibrosis than the HA- and PEG-coated tube groups. CONCLUSIONS: A surface-modified tracheal T-tube may have a favorable effect on reducing tracheal stenosis in a rabbit model. We suggest that local application of HA and PEG should be further researched for prevention of tracheal stenosis. Our rabbit model could be helpful in providing an additional scenario for evaluating new strategies to prevent tracheal stenosis. LEVEL OF EVIDENCE: NA

Characterization of membrane foulants in a pilot-scale tunnel construction wastewater treatment process.

A pilot-scale combination of a microfiltration (MF) and a reverse osmosis (RO) membrane system was applied on-site to treat tunnel construction wastewater. The MF membrane system initially removed contaminants (turbidity of less than 0.3 NTU) in the form of particulate materials in the feed water, thereby allowing the combined MF-RO system to efficiently remove more than 99% of known organic and inorganic contaminants and qualify the reclaimed water for reuse. The MF membrane autopsy analysis using X-ray fluorescence (XRF) and inductively coupled plasma-mass spectrometry (ICP-MS) revealed that the dominant foulants were inorganic deposits involving Si, Al and Fe, comprising the main components of cement materials, as well as deposits involving heavy metals such as Mn, Cu and Zn in the form of particles. Thus, thick cake contaminants shown by field emission scanning electron microscope (FE-SEM) images might be induced via suspended solids consisting of cement and clay materials and metals.

Use of grape seed and its natural polyphenol extracts as a natural organic coagulant for removal of cationic dyes.

Natural organic coagulants (NOCs) such as chitosan and Moringa oleifera seeds have been extensively characterized for potential application in water treatment as an alternative to metal-based coagulants. However, the action of both chitosan and M. oleifera seeds is mainly restricted to anionic organic pollutants because of their cationic functional groups affording poor cationic pollutant coagulation by electrostatic repulsion. In this study, we employed ethanolic grape seed extract (GSE) and grape seed-derived polyphenols such as tannic acid and catechin in an effort to find novel NOCs showing stable anionic forms for removal of cationic organic pollutants. The target substances tested were malachite green (MG) and crystal violet (CV), both mutagenic cationic dyes. Polyphenol treatment induced fast decolorization followed by gradual floc formation concomitant with red or blue shifts in maximum absorbance wavelengths of the cationic dyes. Liquid chromatography analysis of flocs formed by polyphenols directly showed that initial supramolecular complexes attributed mainly to electrostatic attraction between polyphenol hydroxyphenyl groups and cationic dyes further progressed into stronger aggregates, leading to precipitation of dye-polyphenol complexes. Consistent with the results obtained using catechin and tannic acid, use of GSE also resulted in effective decolorization and coagulation of soluble MG and CV in aqueous solutions. Screening of several organic GSE components for NOC activity strongly suggested that natural polyphenols are the main organic ingredients causing MG and CV removal via gradual floc formation. The treatment by natural polyphenols and GSE decreased toxicity of MG- or CV-contaminated water.

Enhanced transformation of malachite green by laccase of Ganoderma lucidum in the presence of natural phenolic compounds.

In this study, we investigated the efficacy of phenolic extract of wheat bran and lignin-related phenolic compounds as natural redox mediators on laccase-mediated transformation of malachite green (MG) using purified laccase from the white-rot fungus Ganoderma lucidum. G. lucidum laccase was able to decolorize 40.7% MG dye (at 25 mg l(-1)) after 24 h of incubation. Whereas, the addition of phenolic extract of wheat bran enhanced the decolorization significantly (p<0.001) by two- to threefold than that of purified laccase alone. Among various natural phenolic compounds, acetovanillone, p-coumaric acid, ferulic acid, syringaldehyde, and vanillin were the most efficient mediators, as effective as the synthetic mediator 1-hydroxybenzotriazole. Characterization of MG transformation products by HPLC, UV-Vis, and liquid chromatography-mass spectrometry-electrospray ionization analysis revealed that N-demethylation was the key mechanism of decolorization of MG by laccase. Growth inhibition test based on mycelial growth inhibition of white rot fungus Phanerochaete chrysosporium revealed that treatment with laccase plus natural mediators effectively reduced the growth inhibitory levels of MG than that of untreated one. Among all the tested compounds, syringaldehyde showed the highest enhanced decolorization, as a consequence reduced growth inhibition was observed in syringaldehyde-treated samples. The results of the present study revealed that the natural phenolic compounds could alternatively be used as potential redox mediators for effective laccase-mediated decolorization of MG.

Alumina femoral head fracture in uncemented total hip arthroplasty with a ceramic sandwich cup.

In total hip arthroplasty, insertion of a UHMWPE-coated ceramic sandwich liner dramatically reduces any risk related to the stiffness of the ceramic-ceramic coupling. We present a case of an alumina ceramic head fracture with a ceramic sandwich cup. The fracture occurred 16 months after the initial operation, without trauma. Impingement between the neck and posteroinferior portion of the liner rim had occurred. This was related to the traditional cross-legged sitting position of Koreans, which caused impingement between the neck and liner rim. Consequently, the taper became loose, and the resulting force bent the taper and fractured the head. We examined a peculiar case of ceramic femoral head fracture after implantation of an uncemented total hip arthroplasty with a ceramic sandwich cup and investigated the underlying cause.

Sialoendoscopic treatment for radioiodine induced sialadenitis.

BACKGROUND AND OBJECTIVE: The use of radioiodine (RI) for the ablation of residual thyroid tissue and metastatic thyroid cancer lesions after thyroidectomy has become established as standard treatment in the management of differentiated thyroid cancer and subsequent sialadenitis is the most common complication of RI therapy. The purpose of this study was to establish a new treatment modality for RI-induced sialadenitis. METHOD: The study group consisted of 115 patients with a mean age of 47.7 (range, 24-78) years. All patients received RI therapy after total thyroidectomy. The incidence of RI-induced sialadenitis, salivary gland involvement, administered RI dose, treatment modality, and result of treatment by interventional sialoendoscopy were evaluated. RESULTS: The incidence of RI-induced sialadenitis was 18% (21/115), with involvement of the parotid more frequent than the submandibular gland. The average development period of RI-induced sialadenitis was 4.8 months. The average RI dosage for the sialadenitis group was higher than for the nonsialadenitis group, suggesting that RI-induced sialadenitis may be dose related, although the data were not statistically significant because of the small numbers in the high-dose group. Conservative management was effective in 71% (15/21) of the cases, and interventional sialoendoscopy was successful in 50% of those cases that did not respond to conservative treatment. The causes of treatment failure in the remaining cases were a totally obstructed parotid duct and stenosis at the bifurcation site. CONCLUSION: Sialadenitis is the most common complication after RI therapy. Sialadenitis was successfully managed by conservative treatment in most cases, and interventional sialoendoscopy is an alternative method of treatment in selected cases such as in partial ductal stenosis.