ABSTRACT
Polyhydroxyalkanoates (PHAs) and their derivatives are biopolymers that have the potential of replacing petroleum-based plastics and can be produced and degraded via bacterial metabolism. However, there are only a few studies on polyhydroxybutyrate (PHB) production using lactate, one of the major waste organic acids that could be implemented in the production of polylactic acid (PLA). Herein, we screened and characterized the PHA-producing microbial strains isolated from saltern soil from Docho Island (South Korea). Among the 24 identified microorganisms that can use lactate as a carbon source, Bacillus sp. YHY22, a newly reported strain, produced the highest amount of PHB: 4.05 g/L with 6.25 g/L dry cell weight, which is 64.7% PHB content under optimal production conditions. Bacillus sp. YHY22 could form the poly(3-hydroxybutyrate-co-3-hydroxyvalerate) copolymer with propionate addition. Moreover, Bacillus sp. YHY22 produced PHB in non-sterilized 2% lactate and 8% NaCl marine broth culture medium, suggesting that its production can occur in high salinity media without additional sterilization steps, rendering fermentation cost- and time-efficient.
Subject(s)
Bacillus , Polyhydroxyalkanoates , Bacillus/metabolism , Biopolymers/metabolism , Hydroxybutyrates/metabolism , Lactic Acid/metabolism , Polyesters/metabolismABSTRACT
Professional practitioners who are required to stand for long periods of time frequently complain about vein-related symptoms. Compression stocking are effective for vein-related symptoms, but there is not enough evidence on the effect of the length of compression stockings for nursing students. To compare oedema, pain, and satisfaction according to different lengths of compression stockings worn by female nursing students. This study was conducted as a randomized clinical trial. The participants included 20 female nursing students in their first semester of clinical practice training. Compression stockings with 25-32 mmHg pressure were used in the study; the participants were divided into two groups based on the length of compression stocking: knee length and thigh length. Differences between groups regarding pain, oedema, and satisfaction were analysed using t-tests, paired t-tests, and Mann-Whitney U tests, when appropriate. There were no significant differences in pain, oedema, and satisfaction between the two groups. However, pain in right legs of the thigh-length stocking group significantly increased after clinical training shift compared with that before the shift (t = -2.377, p = 0.041). Both groups reported high satisfaction. There were no differences in pain, oedema, and satisfaction in both legs based on the length of compression stockings, but side effects appeared in participants wearing the thigh-length stockings; nevertheless, satisfaction was high in both groups. It may be important to suggest nursing students to wear knee-length compression stockings during clinical practice training.
ABSTRACT
A hydrothermally synthesized rhodium/antimony co-doped TiO2 nanorod and titanate nanotube (RS-TONR/TNT) composite was prepared for removal of heavy metals and organic pollutants from water under visible light irradiation. The composite provides the dual function of simultaneous adsorption of heavy metal ions and enhanced degradation of dissolved organic compounds. Acid treatment transformed titanate nanotubes to irregular tubular structures distributed homogeneously over untransformed RS/TONRs. Synergistic removal and degradation was studied with various heavy metals, Orange (II) dye, and Bisphenol A. The adsorption capacity of the composite for heavy metal ions was Pb(II)â¯>â¯Cd(II)â¯>â¯Cu(II)â¯>â¯Zn(II). The adsorbed metals enhanced photocatalytic degradation of the organic pollutants, but Cu was most effective, with degradation exceeding 70% for the dye and 80% for Bisphenol A after 5â¯h of treatment. Photocatalytic activity was enhanced more by adsorption than photodeposition of Cu ions. A decrease in XRD rutile peak intensity with adsorbed metal indicates a change in crystallinity which may enhance photocatalytic activity. Thick and bulging nanostructures in FE-SEM images signify ion adsorption within titanate pores. BET analysis indicated titanate nanotubes with adsorbed metal are mesoporous but their tubular structure persists. XPS showed more active Cu 2p3/2 states under light, supporting an active role of Cu+ in photocatalytic ROS generation. Detection of ROS and Cu species using methanol, EDTA, pCBA, and benzoic acid probes provided strong evidence for degradation via a charge transfer mechanism. Findings demonstrate the potential of the RS-TONR/TNT composite for simultaneous removal of heavy metals and degradation of organic pollutants.
Subject(s)
Metals, Heavy , Trinitrotoluene , Water Pollutants, Chemical , Adsorption , LightABSTRACT
This study presents the first report on the photocatalytic inactivation mechanism for a Salmonella typhimurium pathogen by visible-light active CuxO loaded rhodium-antimony co-doped TiO2 nanorods (CuxO/Rh-Sb-TiO2 NRs) under visible light irradiation (cutoff filter, λ ≥ 420 nm). Remarkably higher pathogenic inactivation of 4 log within 40 min by a CuxO supported Rh-Sb-TiO2 NR photocatalyst was observed. The visible light active photocatalyst mainly produced reduced Cu+ in the lattice of CuxO by charge separation. By this means, photo-generated electrons at the conduction band of Rh-Sb-TiO2 NRs play an important role in reducing Cu2+ to Cu+ through the photocatalytic reduction reaction (PRR), and at the valence band of Rh-Sb-TiO2 NRs, photo-generated holes generate OHË radicals through the photocatalytic oxidation reaction (POR). This Cu+ copper species is lethal to microbial pathogens. The inactivation mechanism for the Salmonella typhimurium pathogen was investigated by protein oxidation, HCHO production, and the API-ZYM system. To investigate the role of OHË radicals, t-BuOH and MeOH as hole scavengers were used in photocatalytic inactivation reactions. Our experimental results confirmed that the reduced Cu+ species play a major role in bacterial inactivation, while ROS have a major effect on the degradation of organic pollutants.
Subject(s)
Anti-Bacterial Agents/pharmacology , Antimony/pharmacology , Copper/pharmacology , Rhodium/pharmacology , Salmonella typhimurium/drug effects , Titanium/pharmacology , Anti-Bacterial Agents/chemistry , Antimony/chemistry , Catalysis , Copper/chemistry , Light , Nanotubes/chemistry , Photochemical Processes , Rhodium/chemistry , Salmonella typhimurium/metabolism , Titanium/chemistryABSTRACT
BACKGROUND: Being common, mild anemia is sometimes considered a mere consequence of aging; however, aging alone is unlikely to lead to anemia. Therefore, this study aimed to investigate the association between mild anemia and total mortality and cause-specific mortality in apparently healthy elderly subjects. METHODS: A retrospective cohort study was conducted on 10,114 apparently healthy elderly individuals who underwent cancer screening and routine medical check-ups at one Health Promotion Center between May 1995 and December 2007. We defined mild anemia as a hemoglobin concentration between 10.0 g/dL and 11.9 g/dL in women and between 10.0 g/dL and 12.9 g/dL in men. We assessed the relationship between the overall, cardiovascular (CV), and cancer mortality and mild anemia using Cox proportional hazard models. RESULTS: Mild anemia was present in 143 men (3.1%) and 246 women (6.1%). During an average follow-up of 7.6 years, 495 deaths occurred, including 121 CV and 225 cancer deaths. After adjustments, mild anemia was associated with a 128% increase in the risk of all-cause mortality hazard ratio (HR, 2.28; 95% confidence interval [CI], 1.54- 3.37) in men and cancer-related mortality (HR, 2.25; 95% CI, 1.22-4.13), particularly lung cancer (HR, 2.70; 95% CI, 1.03-7.08) in men, but not in women. In the subgroup analyses based on smoking status, obesity, and age, the associations were more prominent in never or former smoker groups and the older group. CONCLUSION: The present study shows that overall and cancer-related mortality was associated with mild anemia in elderly men. Future prospective studies are needed to consolidate our findings.
ABSTRACT
OBJECTIVES: The purpose of this study was to find out validity of Surface Electromyography(sEMG) compared with Nerve Conduction Study and clinical assessment scale as assessment factors for facial palsy. METHODS: We investigated 50 cases of patients with peripheral facial palsy who had records of sEMG and NCS to check. Then we analyzed the correlation between sEMG and NCS that carried out around 1 week after onset. And we analyzed the correlation between sEMG and clinical assessment scales that were measured three times around 1 week, 3-4 weeks and 5-6 weeks after onset. Clinical assessment scales used in this study were House-brackmann grade, Yanagihara unweighted grading scale and Sunnybrook facial grading system. We used Pearson's correlation for statistical analysis. RESULTS: sEMG and NCS, measured at similar times, were statistically correlated. Especially, the correlation with the forehead region was high. And sEMG and clinical assessment scale, measured at same time, were statistically correlated, especially after 5 weeks from onset. CONCLUSION: According to this study, sEMG is expected to be useful to assessment facial palsy.
ABSTRACT
In the present work, we accomplish the boosting of photocatalytic performance by the synergistic effect of acid treatment and transition metal oxide co-catalysts on molten salt rutile TiO2 nanorods. FT-IR and XPS (oxygen deconvolution) results confirmed that the amount of hydroxyl groups increased on the surface of rutile TiO2 nanorods (TO-NRs) after acid treatment. HR-TEM analysis revealed fine dispersion of metal oxide on the surface of acid treated TiO2 nanorods (ATO-NRs). The photocatalytic activities of as-prepared (TO-NRs), acid treated (ATO-NRs), metal oxide loaded (MTO-NRs), and both acid treated and metal oxide loaded (MATO-NRs) nanorods were compared based on the rate kinetics and dye degradation efficiencies. Cobalt oxide (1 wt %) loaded and 1.0 M acid treated TiO2 nanorods (Co/ATO-NR) exhibited the higher photocatalytic degradation efficiency for Orange-II dye degradation and inactivation of S. typhimurium pathogen compared to other photocatalysts under solar irradiation. Photoelectrochemical analysis demonstrated that the charge transfer process in Co/ATO-NR is significantly higher than that in the untreated samples. The improved photocatalytic activity of inactive TO-NRs might be due to enhanced charge transfer of finely dispersed metal oxides on the OH-rich surface of acid treated TiO2 nanorods.
ABSTRACT
This study was designed to investigate the cooperative effect of selected Lactobacillus gasseri strains and Cudrania tricuspidata (CT) leaf extract in enhancing the health-promoting activities of fermented milk. Addition of CT increased total bacterial counts and proteolysis during fermentation of milk with L. gasseri strains. Antioxidant capacities were determined by measuring the ABTS, DPPH, and peroxyl radical scavenging activities and ferric reducing power. The antioxidant capacity of CT-supplemented milk was greater than that of milk without supplementation; moreover, the antioxidant activity of CT-supplemented milk was synergistically improved by fermentation with L. gasseri strains. In particular, CT-supplemented milk fermented by L. gasseri 505 showed the highest antioxidant activity. The phenolic compounds in CT, such as neo-chlorogenic, chlorogenic, and caffeic acid, were metabolized during fermentation with L. gasseri strains, and 3,4-dihydroxy-hydrocinnamic acid was produced as a fermentation metabolite. Moreover, the liberation of bioactive peptides of fermented milk was increased by the proteolytic activity of L. gasseri strains. In particular, six peptides, which were mainly derived from ß-casein, were newly identified in this study. These findings suggest that L. gasseri strains metabolize the phenolic acids in the CT and the bioactive peptides released through this interaction improve the antioxidant activity of the fermented milk.
Subject(s)
Cultured Milk Products/microbiology , Lactobacillus gasseri/metabolism , Moraceae/metabolism , Plant Extracts/metabolism , Animals , Antioxidants/metabolism , Caseins/metabolism , Cattle , Cultured Milk Products/analysis , Fermentation , Functional Food/analysis , Functional Food/microbiology , Plant Leaves/metabolism , Synbiotics/administration & dosage , Synbiotics/analysisABSTRACT
Determining the exact duration of seizure activity is an important factor for predicting the efficacy of electroconvulsive therapy (ECT). In most cases, seizure duration is estimated manually by observing the electroencephalogram (EEG) waveform. In this article, we propose a method based on sample entropy (SampEn) that automatically detects the termination time of an ECT-induced seizure. SampEn decreases during seizure activity and has its smallest value at the boundary of seizure termination. SampEn reflects not only different states of regularity and complexity in the EEG but also changes in EEG amplitude before and after seizure activity. Using SampEn, we can more precisely determine seizure termination time and total seizure duration.
Subject(s)
Electroencephalography/methods , Electronic Data Processing/methods , Entropy , Outcome Assessment, Health Care/methods , Seizures/physiopathology , Electroconvulsive Therapy/methods , Fourier Analysis , Humans , Seizures/therapy , Time FactorsABSTRACT
Methylenetetrahydrofolate reductase (MTHFR), a critical enzyme in folate metabolism, plays an important role in DNA methylation. It has been suggested that abnormal DNA methylation contributes to the pathogenesis of schizophrenia and congenital anomalies. The previous findings regarding the genetic relationship between MTHFR and schizophrenia are controversial. This study investigated the association of the two functional polymorphisms of MTHFR, C677T and A1298C, with the risk for schizophrenia. Furthermore, we conducted an updated meta-analysis on the two polymorphisms. In addition, we investigated the relationship between the polymorphisms and minor physical anomaly (MPA), which may represent neurodevelopmental aberrations in 201 schizophrenia patients and 350 normal control subjects. There was no significant association between either of the two polymorphisms and the risk of schizophrenia (chi-square = 0.001, df = 1, P = 0.971 for C677T; chi-square = 1.319, df = 1, P = 0.251 for A1298C). However, in meta-analysis, the C677T polymorphism showed a significant association in the combined and Asian populations (OR = 1.13, P = 0.005; OR = 1.21, P = 0.011, respectively) but not in the Korean and Caucasian populations alone. Neither polymorphism was associated with MPAs measured by the Waldrop scale (chi-square = 2.513, df = 2, P = 0.285). In conclusion, the present findings suggest that in the Korean population, the MTHFR polymorphisms are unlikely to be associated with the risk for schizophrenia and neurodevelopmental abnormalities related to schizophrenia.
Subject(s)
Congenital Abnormalities/genetics , Methylenetetrahydrofolate Reductase (NADPH2)/genetics , Polymorphism, Single Nucleotide , Schizophrenia/genetics , Adult , Alleles , Case-Control Studies , DNA Methylation , Female , Gene Frequency , Genetic Association Studies , Genetic Predisposition to Disease , Genotype , Humans , Male , Middle Aged , Republic of Korea , Schizophrenia/pathologyABSTRACT
V-akt murine thymoma viral oncogene homolog 1 (AKT1) has been suggested to be involved in the pathophysiology of schizophrenia. Recent, independent studies in Caucasian, Japanese, Iranian, and Chinese populations have reported that the AKT1 gene may be associated with schizophrenia, but these results have yet to be replicated in other populations. In the present study, we performed a case-control association study between AKT1 and schizophrenia in a Korean population. We genotyped six single nucleotide polymorphisms (SNP1 (rs3803300), SNP2 (rs1130214), SNP3 (rs3730358), SNP4 (rs1130233), SNP5 (rs2494732), SNP A (rs2498804)) of AKT1, selected from previous reports, in a sample of 283 subjects with schizophrenia and 350 controls. No significant difference in single marker polymorphisms or haplotype frequencies of the six SNPs in the AKT1 gene was observed between controls and subjects with schizophrenia. In addition, we carried out an updated meta-analysis of the six SNPs, and found no evidence for an association between the six SNPs and schizophrenia. Taken together, our results do not support the hypothesis that AKT1 is a susceptibility gene for schizophrenia.
Subject(s)
Asian People/genetics , Polymorphism, Single Nucleotide , Proto-Oncogene Proteins c-akt/genetics , Schizophrenia/genetics , Adult , Case-Control Studies , Female , Gene Frequency , Genetic Association Studies , Haplotypes , Humans , Korea , Linkage Disequilibrium , Male , Odds RatioABSTRACT
The cardiac autonomic dysfunction has been reported in patients with schizophrenia. Heart rate variability (HRV) provides non-invasive indices of cardiac autonomic modulation. This study examined whether patients with schizophrenia may show a distinctive pattern of HRV compared to healthy controls. Nine measures of time, frequency and complexity domains were extracted from 5-min resting evaluation of HRV in 30 unmedicated patients with schizophrenia and 30 age- and gender-matched controls. In addition to inferential statistics, a hierarchical clustering (HC) was used to examine difference in the interrelationships among HRV measures between the two groups. Multivariate analysis of variance revealed a significant group effect. Significantly lower sample entropy (SampEn) and a trend towards a higher ratio of low- to high frequency (LF/HF) were observed in the schizophrenia group. In the results of HC using Ward's method, SampEn co-clustered with LF/HF ratio in patients with schizophrenia compared to the separation of LF/HF ratio in healthy controls. In concert with decreased parasympathetic activity, low complexity of heart rate dynamics may reduce adaptability of cardiovascular system to changes in internal or external environment, thus increasing the risk of cardiovascular events. Diverse HRV measures combined in a multivariate fashion appear to be useful in understanding the pattern of neurocardiac modulation in patients with schizophrenia.