Genome-wide function of MCM-BP in Trypanosoma brucei DNA replication and transcription.

In Trypanosoma brucei, genes are arranged in Polycistronic Transcription Units (PTUs), which are demarcated by transcription start and stop sites. Transcription start sites are also binding sites of Origin Recognition Complex 1 (ORC1). This spatial coincidence implies that transcription and replication in trypanosomes must occur in a highly ordered and cooperative manner. Interestingly, a previously published genetic screen identified the T. brucei MCM-BP, which interacts with subunits of MCM helicase, as a protein whose downregulation results in the loss of transcriptional silencing at subtelomeric loci. Here, I show that TbMCM-BP is required for DNA replication and transcription. TbMCM-BP depletion causes a significant reduction of replicating cells in S phase and genome-wide impairments of replication origin activation. Moreover, levels of sense and antisense transcripts increase at boundaries of PTUs in the absence of TbMCM-BP. TbMCM-BP is also important for transcriptional repression of the specialized subtelomeric PTUs, the Bloodstream-form Expression-Sites (BESs), which house the major antigenic determinant (the Variant Surface Glycoprotein, VSG gene) as well as TbORC1 binding sites. Overall, this study reveals that TbMCM-BP, a replication initiation protein, also guides the initiation, termination and directionality of transcription.

Base J and H3.V Regulate Transcriptional Termination in Trypanosoma brucei.

Trypanosoma brucei is a protozoan parasite that lacks many transcription factors found in other eukaryotes, such as those whose binding demarcates enhancers. T. brucei retains histone variants and modifications, however, and it is hypothesized that it relies on epigenetic marks to define transcription-related boundaries. The histone H3 variant (H3.V) and an alternate nucleotide, base J (ß-D-glucosyl-hydroxymethyluracil), are two chromatin marks found at both transcription termination sites (TTSs) and telomeres. Here, we report that the absence of both base J and H3.V result in transcription readthrough and the appearance of antisense transcripts near TTSs. Additionally, we find that maintaining the transcriptional silencing of pol I-transcribed telomeric Variant Surface Glycoprotein (VSG) genes appears to be dependent on deposition of H3.V alone. Our study reveals that gene expression depends on different epigenetic cues depending on chromosomal location and on the transcribing polymerase. This work provides insight into how these signals may have evolved into the more nuanced and fine-tuned gene regulatory mechanisms observed in other model systems.

Bromodomain Proteins Contribute to Maintenance of Bloodstream Form Stage Identity in the African Trypanosome.

Trypanosoma brucei, the causative agent of African sleeping sickness, is transmitted to its mammalian host by the tsetse. In the fly, the parasite's surface is covered with invariant procyclin, while in the mammal it resides extracellularly in its bloodstream form (BF) and is densely covered with highly immunogenic Variant Surface Glycoprotein (VSG). In the BF, the parasite varies this highly immunogenic surface VSG using a repertoire of ~2500 distinct VSG genes. Recent reports in mammalian systems point to a role for histone acetyl-lysine recognizing bromodomain proteins in the maintenance of stem cell fate, leading us to hypothesize that bromodomain proteins may maintain the BF cell fate in trypanosomes. Using small-molecule inhibitors and genetic mutants for individual bromodomain proteins, we performed RNA-seq experiments that revealed changes in the transcriptome similar to those seen in cells differentiating from the BF to the insect stage. This was recapitulated at the protein level by the appearance of insect-stage proteins on the cell surface. Furthermore, bromodomain inhibition disrupts two major BF-specific immune evasion mechanisms that trypanosomes harness to evade mammalian host antibody responses. First, monoallelic expression of the antigenically varied VSG is disrupted. Second, rapid internalization of antibodies bound to VSG on the surface of the trypanosome is blocked. Thus, our studies reveal a role for trypanosome bromodomain proteins in maintaining bloodstream stage identity and immune evasion. Importantly, bromodomain inhibition leads to a decrease in virulence in a mouse model of infection, establishing these proteins as potential therapeutic drug targets for trypanosomiasis. Our 1.25Å resolution crystal structure of a trypanosome bromodomain in complex with I-BET151 reveals a novel binding mode of the inhibitor, which serves as a promising starting point for rational drug design.

The General Public's Awareness of Early Symptoms of and Emergency Responses to Acute Myocardial Infarction and Related Factors in South Korea: A National Public Telephone Survey.

BACKGROUND: Prompt treatment affects prognosis and survival after acute myocardial infarction (AMI) onset. This study evaluated the awareness of early symptoms of AMI and knowledge of appropriate responses on symptom occurrence, along with related factors. METHODS: Participants' knowledge of the early symptoms of and responses to AMI onset were investigated using a random digit dialing survey. We included 9600 residents of 16 metropolitan cities and provinces in Korea. RESULTS: The proportions of respondents who were aware of early symptoms of AMI ranged from 32.9% (arm or shoulder pain) to 79.1% (chest pain and discomfort). Of the respondents, 67.0% would call an ambulance if someone showed signs of AMI, 88.7% knew ≥1 symptom, 10.9% knew all five symptoms, and 3.1% had excellent knowledge (correct identification of all five AMI symptoms, not answering "Yes" to the trap question, and correctly identifying calling an ambulance as the appropriate response when someone is exhibiting AMI symptoms). The odds ratio (OR) for having excellent knowledge was significantly higher for those who graduated college or higher (OR 3.42; 95% confidence interval [CI], 1.09-10.76) than for those with less than a primary school education, as well as for subjects with AMI advertisement exposure (OR 1.49; 95% CI, 1.10-2.02) and with knowledge of AMI (OR 1.63; 95% CI, 1.16-2.27). The 60- to 79-year-old group had significantly lower OR for excellent knowledge than the 20- to 39-year-old group (OR 0.53; 95% CI, 0.28-0.99). CONCLUSIONS: Awareness of AMI symptoms and the appropriate action to take after symptom onset in South Korea was poor. Therefore, educational and promotional strategies to increase the overall awareness in the general public, especially in the elderly and those with low education levels, are needed.

Public Awareness of Stroke and Its Predicting Factors in Korea: a National Public Telephone Survey, 2012 and 2014.

The aim of this study was to investigate time trends in the public awareness of stroke and its predicting factors. The target population was 9,600 community-dwelling adults, aged 19-79 years, in 16 metropolitan cities and provinces in Korea. The survey samples in 2012 and 2014 were selected separately (entirely different sets of subjects) using a proportionate quota sampling method. Information concerning knowledge of stroke and demographics was collected by trained telephone interviewers using random digit dialing. After excluding subjects with a non-response or refusal to answer any question, the analyses included 8,191 subjects in 2012 and 8,127 subjects in 2014. Respondents' awareness of stroke warning signs (numbness or weakness, difficulty speaking or understanding speech, dizziness, visual impairment, and severe headache) was highest for difficulty speaking or understanding speech (80.9% in 2012 and 86.4% in 2014). There were significant increases in the proportion of respondents understanding the appropriate action (i.e., calling an ambulance) at the time of stroke occurrence (59.6% to 67.1%), and in the proportion aware of the general need for prompt treatment (86.7% to 89.8%). In multivariable logistic regression analysis, older age, higher education level, higher household income, current non-smoking, exposure to stroke-related public relations materials, and experience of stroke education were significantly associated with both high knowledge of stroke warning signs and awareness of the need for prompt treatment. Between 2012 and 2014, the public's awareness of stroke increased significantly. More specialized interventions, including public relations materials and education, should focus on subgroups who have lower stroke knowledge.

Characterization of a flavin-containing monooxygenase from Corynebacterium glutamicum and its application to production of indigo and indirubin.

OBJECTIVE: To examine the role of a gene encoding flavin-containing monooxygenase (cFMO) from Corynebacterium glutamicum ATCC13032 when cloned and expressed in Escherichia coli for the production of indigo pigments. RESULTS: The blue pigments produced by recombinant E. coli were identified as indigo and indirubin. The cFMO was purified as a fused form with maltose-binding protein (MBP). The enzyme was optimal at 25 °C and pH 8. From absorption spectrum analysis, the cFMO was classified as a flavoprotein. FMO activity was strongly inhibited by 1 mM Cu(2+) and recovered by adding 1-10 mM EDTA. The enzyme catalyzed the oxidation of TMA, thiourea, and cysteamine, but not glutathione or cysteine. MBP-cFMO had an indole oxygenase activity through oxygenation of indole to indoxyl. The recombinant E. coli produced 685 mg indigo l(-1) and 103 mg indirubin l(-1) from 2.5 g L-tryptophan l(-1). CONCLUSION: The results suggest the cFMO can be used for the microbial production of both indigo and indirubin.

Trypanosoma brucei Orc1 is essential for nuclear DNA replication and affects both VSG silencing and VSG switching.

Binding of the Origin Recognition Complex (ORC) to replication origins is essential for initiation of DNA replication, but ORC has non-essential functions outside of DNA replication, including in heterochromatic gene silencing and telomere maintenance. Trypanosoma brucei, a protozoan parasite that causes human African trypanosomiasis, uses antigenic variation as a major virulence mechanism to evade the host's immune attack by expressing its major surface antigen, the Variant Surface Glycoprotein (VSG), in a monoallelic manner. An Orc1/Cdc6 homologue has been identified in T. brucei, but its role in DNA replication has not been directly confirmed and its potential involvement in VSG repression or switching has not been thoroughly investigated. In this study, we show that TbOrc1 is essential for nuclear DNA replication in mammalian-infectious bloodstream and tsetse procyclic forms (BF and PF). Depletion of TbOrc1 resulted in derepression of telomere-linked silent VSGs in both BF and PF, and increased VSG switching particularly through the in situ transcriptional switching mechanism. TbOrc1 associates with telomere repeats but appears to do so independently of two known T. brucei telomere proteins, TbRAP1 and TbTRF. We conclude that TbOrc1 has conserved functions in DNA replication and is also required to control telomere-linked VSG expression and VSG switching.

Molecular cloning and characterization of a novel acetylalginate esterase gene in alg operon from Sphingomonas sp. MJ-3.

A novel acetylalginate esterase (AcAlgE) gene was cloned and characterized from the genomic DNA library of Sphingomonas sp. MJ-3. A putative gene encoding AcAlgE protein of 292-residue precursor protein with 20-amino acid signal peptide was identified in the alg operon. The deduced AcAlgE protein has GDSL-like consensus motif and shares a highest sequence identity (51%) with GDSL family lipolytic protein from Pseudoxanthomonas suwonensis. Enzymatic assays with bacterial acetylalginate as the substrate showed that the recombinant AcAlgE protein possesses deacetylation activity. The optimal temperature and pH for the AcAlgE were 22 °C and pH 6.5 (citrate buffer), respectively. The recombinant AcAlgE protein catalyzed deacetylation of acetylalginate with release of acetate. The resulting de-acetylated alginate was readily degraded by alginate lyases, indicating that the recombinant AcAlgE enhanced the subsequent degradation of acetylalginate by alginate lyases. The recombinant AcAlgE can play an important role in the degradation of acetylated alginate such as mucoidal acetylalginate in cystic fibrosis patient.

Trends in the incidence of hospitalized acute myocardial infarction and stroke in Korea, 2006-2010.

This study attempted to calculate and investigate the incidence of hospitalized acute myocardial infarction (AMI) and stroke in Korea. Using the National Health Insurance claim data, we investigated patients whose main diagnostic codes included AMI or stroke during 2006 to 2010. As a result, we found out that the number of AMI hospitalized patients had decreased since 2006 and amounted to 15,893 in 2010; and that the number of those with stroke had decreased since 2006 and amounted to 73,501 in 2010. The age-standardized incidence rate of hospitalized AMI, after adjustment for readmission, was 41.6 cases per 100,000-population in 2006, and had decreased to 29.4 cases in 2010 (for trend P < 0.001). In the case of stroke was estimated at 172.8 cases per 100,000-population in 2006, and had decreased to 135.1 cases in 2010 (for trend P < 0.001). In conclusion, the age-standardized incidence rates of both hospitalized AMI and stroke in Korea had decreased continuously during 2006 to 2010. We consider this decreasing trend due to the active use of pharmaceuticals, early vascular intervention, and the national cardio-cerebrovascular disease care project as the primary and secondary prevention efforts.

Identification of a small-molecule inhibitor that selectively blocks DNA-binding by Trypanosoma brucei replication protein A1.

Replication Protein A (RPA) is a broadly conserved complex comprised of the RPA1, 2 and 3 subunits. RPA protects the exposed single-stranded DNA (ssDNA) during DNA replication and repair. Using structural modeling, we discover an inhibitor, JC-229, that targets RPA1 in Trypanosoma brucei, the causative parasite of African trypanosomiasis. The inhibitor is highly toxic to T. brucei cells, while mildly toxic to human cells. JC-229 treatment mimics the effects of TbRPA1 depletion, including DNA replication inhibition and DNA damage accumulation. In-vitro ssDNA-binding assays demonstrate that JC-229 inhibits the activity of TbRPA1, but not the human ortholog. Indeed, despite the high sequence identity with T. cruzi and Leishmania RPA1, JC-229 only impacts the ssDNA-binding activity of TbRPA1. Site-directed mutagenesis confirms that the DNA-Binding Domain A (DBD-A) in TbRPA1 contains a JC-229 binding pocket. Residue Serine 105 determines specific binding and inhibition of TbRPA1 but not T. cruzi and Leishmania RPA1. Our data suggest a path toward developing and testing highly specific inhibitors for the treatment of African trypanosomiasis.

TOPO3alpha influences antigenic variation by monitoring expression-site-associated VSG switching in Trypanosoma brucei.

Homologous recombination (HR) mediates one of the major mechanisms of trypanosome antigenic variation by placing a different variant surface glycoprotein (VSG) gene under the control of the active expression site (ES). It is believed that the majority of VSG switching events occur by duplicative gene conversion, but only a few DNA repair genes that are central to HR have been assigned a role in this process. Gene conversion events that are associated with crossover are rarely seen in VSG switching, similar to mitotic HR. In other organisms, TOPO3alpha (Top3 in yeasts), a type IA topoisomerase, is part of a complex that is involved in the suppression of crossovers. We therefore asked whether a related mechanism might suppress VSG recombination. Using a set of reliable recombination and switching assays that could score individual switching mechanisms, we discovered that TOPO3alpha function is conserved in Trypanosoma brucei and that TOPO3alpha plays a critical role in antigenic switching. Switching frequency increased 10-40-fold in the absence of TOPO3alpha and this hyper-switching phenotype required RAD51. Moreover, the preference of 70-bp repeats for VSG recombination was mitigated, while homology regions elsewhere in ES were highly favored, in the absence of TOPO3alpha. Our data suggest that TOPO3alpha may remove undesirable recombination intermediates constantly arising between active and silent ESs, thereby balancing ES integrity against VSG recombination.

Molecular cloning, purification, and characterization of a novel polyMG-specific alginate lyase responsible for alginate MG block degradation in Stenotrophomas maltophilia KJ-2.

A gene for a polyMG-specific alginate lyase possessing a novel structure was identified and cloned from Stenotrophomas maltophilia KJ-2 by using PCR with homologous nucleotide sequences-based primers. The recombinant alginate lyase consisting of 475 amino acids was purified on Ni-Sepharose column and exhibited the highest activity at pH 8 and 40 °C. Interestingly, the recombinant alginate lyase was expected to have a similar catalytic active site of chondroitin B lyase but did not show chondroitin lyase activity. In the test of substrate specificity, the recombinant alginate lyase preferentially degraded the glycosidic bond of polyMG-block than polyM-block and polyG-block. The chemical structures of the degraded alginate oligosaccharides were elucidated to have mannuronate (M) at the reducing end on the basis of NMR analysis, supporting that KJ-2 polyMG-specific alginate lyase preferably degraded the glycosidic bond in M-G linkage than that in G-M linkage. The KJ-2 polyMG-specific alginate lyase can be used in combination with other alginate lyases for a synergistic saccharification of alginate.

Mepivacaine-induced contraction is attenuated by endothelial nitric oxide release in isolated rat aorta.

Mepivacaine is an aminoamide-linked local anesthetic with an intermediate duration that intrinsically produces vasoconstriction both in vivo and in vitro. The aims of this in-vitro study were to examine the direct effect of mepivacaine in isolated rat aortic rings and to determine the associated cellular mechanism with a particular focus on endothelium-derived vasodilators, which modulate vascular tone. In the aortic rings with or without endothelium, cumulative mepivacaine concentration-response curves were generated in the presence or absence of the following antagonists: N(ω)-nitro-L-arginine methyl ester [L-NAME], indomethacin, fluconazole, methylene blue, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one [ODQ], verapamil, and calcium-free Krebs solution. Mepivacaine produced vasoconstriction at low concentrations (1 × 10(-3) and 3 × 10(-3) mol/L) followed by vasodilation at a high concentration (1 × 10(-2) mol/L). The mepivacaine-induced contraction was higher in endothelium-denuded aortae than in endothelium-intact aortae. Pretreatment with L-NAME, ODQ, and methylene blue enhanced mepivacaine-induced contraction in the endothelium-intact rings, whereas fluconazole had no effect. Indomethacin slightly attenuated mepivacaine-induced contraction, whereas verapamil and calcium-free Krebs solution more strongly attenuated this contraction. The vasoconstriction induced by mepivacaine is attenuated mainly by the endothelial nitric oxide - cyclic guanosine monophosphate pathway. In addition, mepivacaine-induced contraction involves cyclooxygenase pathway activation and extracellular calcium influx via voltage-operated calcium channels.

Ethanol extract of Prunella vulgaris var. lilacina inhibits HMGB1 release by induction of heme oxygenase-1 in LPS-activated RAW 264.7 cells and CLP-induced septic mice.

The ethanol extract of the flower of P. vulgaris var. lilacina (EEPV) has been used traditionally as an antiinflammatory agent in many countries. Inducers of heme oxygenase-1 (HO-1) reduce high mobility group box 1 (HMGB1), a late phase cytokine, in sepsis. Although EEPV has been used as an antiinflammatory agent, no report is available as to whether it modifies HMGB1 in sepsis due to HO-1 induction. It was found that EEPV increased HO-1 protein expression in RAW 264.7 cells, which was significantly inhibited by LY294002, but not PD98059, SB203580 or SP600125. In addition, EEPV activated NF-E2-related factor (Nrf2) to move from the cytosol to the nucleus, and EEPV-induced HO-1 and activation of ARE-luciferase activity were significantly reduced by siNrf2 transfection and LY294002 but not SB203508. EEPV also significantly inhibited NF-κB luciferase activity, and decreased both iNOS/NO and COX-2/PGE(2) production in lipopolysaccharide (LPS)-stimulated macrophages which was reversed by siHO-1 RNA transfection. Importantly, EEPV inhibited HMGB1 release in LPS-activated macrophages in a PI3K-sensitive manner and reduced serum HMGB1 level and lung HMGB1 expression in cecal ligation and puncture (CLP)-induced septic mice. It is concluded that EEPV induces HO-1 expression through PI3K/Nrf2 signal pathways, which may be beneficial for the treatment of sepsis due to a reduction of HMGB1 release.

Molecular identification of a polyM-specific alginate lyase from Pseudomonas sp. strain KS-408 for degradation of glycosidic linkages between two mannuronates or mannuronate and guluronate in alginate.

An alginate lyase gene of a newly isolated Pseudomonas sp. strain KS-408 was cloned by using PCR with the specific primers designed from homologous nucleotide sequences. A partial protein sequence of KS-408 alginate lyase was homology-modeled on the basis of the crystal structure of A1-III alginate lyase from Sphingomonas sp. strain A1. The proposed 3-D structure of KS-408 alginate lyase shows that Asn-198, His-199, Arg-246, and Tyr-253 residues are conserved for the catalytic active site. The recombinant KS-408-1F (with signal peptide) and KS-408-2F (without signal peptide) alginate lyases with the (His)(6) tag consist of 393 (44.5 kDa) and 372 (42.4 kDa) amino acids with isoelectric points of 8.64 and 8.46, respectively. The purified recombinant KS-408 alginate lyase was very stable when it was incubated at 40 °C for 30 min. Alginate oligosaccharides produced by the KS-408-2F alginate lyase were purified on a Bio-Gel P2 column and analyzed by thin-layer chromatography, fast-protein liquid chromatography, and electrospray ionization mass spectrometry. (1)H NMR data showed that the KS-408-2F alginate lyase cleaved the glycosidic linkages between two mannuronates (mannuronate-ß(1-4)-mannuronate) or mannuronate and guluronate (mannuronate-ß(1-4)-guluronate), indicating that the KS-408 alginate lyase is a polyM-specific lyase.

Heterologous expression of an alginate lyase from Streptomyces sp. ALG-5 in Escherichia coli and its use for preparation of the magnetic nanoparticle-immobilized enzymes.

The marine alginate lyase from Streptomyces sp. ALG-5, which specifically degrades poly-G block of alginate, was functionally expressed as a His-tagged form with an Escherichia coli expression system. The recombinant alginate lyase expressed with pColdI at 15 °C exhibited the highest alginate-degrading activity. The recombinant alginate lyase was efficiently immobilized onto two types of magnetic nanoparticles, superparamagnetic iron oxide nanoparticle, and hybrid magnetic silica nanoparticle, based on the affinity between His-tag and Ni(2+) that displayed on the surfaces of nanoparticles. An alginate oligosaccharide mixture consisting of dimer and trimer was prepared by the immobilized alginate lyase. The immobilized enzymes were re-used repeatedly more than 10 times after magnetic separation.

Genetic Interaction Between Site-Specific Epigenetic Marks and Roles of H4v in Transcription Termination in Trypanosoma brucei.

In Trypanosoma brucei, genes are assembled in polycistronic transcription units (PTUs). Boundaries of PTUs are designated transcription start sites and transcription termination sites (TTSs). Messenger RNAs are generated by trans-splicing and polyadenylation of precursor RNAs, and regulatory information in the 3' un-translated region (UTR), rather than promoter activity/sequence-specific transcription factors, controls mRNA levels. Given this peculiar genome structure, special strategies must be utilized to control transcription in T. brucei. TTSs are deposition sites for three non-essential chromatin factors-two of non-canonical histone variants (H3v and H4v) and a DNA modification (base J, which is a hydroxyl-glucosyl dT). This association generated the hypothesis that these three chromatin marks define a transcription termination site in T. brucei. Using a panel of null mutants lacking H3v, H4v, and base J, here I show that H4v is a major sign for transcription termination at TTSs. While having a secondary function at TTSs, H3v is important for monoallelic transcription of telomeric antigen genes. The simultaneous absence of both histone variants leads to proliferation and replication defects, which are exacerbated by the J absence, accompanied by accumulation of sub-G1 population. Thus, I propose that the coordinated actions of H3v, H4v, and J provide compensatory mechanisms for each other in chromatin organization, transcription, replication, and cell-cycle progression.

Age-Period-Cohort Analysis of Trends in Infectious Disease Mortality in South Korea from 1983 to 2017.

We aimed to describe the infectious disease (ID) mortality trends and evaluate age-period-cohort (APC) effects on ID mortality in Korea. Using cause-of-death and census population estimates data from 1983-2017, age-standardized ID mortality trends were investigated by joinpoint regression analysis. The APC effects on ID mortality were estimated using intrinsic estimator models. The age effect showed a J-shaped concave upward curve. Old age, especially ≥70 years, was a critical factor for ID deaths. Similar to the W-shaped period curve, ID mortality rapidly decreased due to economic development and the expansion of health coverage in the 1980s, decelerated with increasing inequality, surged due to the 1997 economic crisis, and has gradually increased since the mid-2000s. The cohort effect showed an inverted U-shape. The increasing cohort effect due to the deterioration of living standards led to a decreasing trend after the independence of Korea. Notwithstanding the slowdown during the 1950-1953 Korean War, educational expansion, economic growth, fertility reduction, and the improvement of ID-related policies might have led to a continued decline among the cohorts born since the 1960s. Diverse socioeconomic events may have influenced ID mortality trends in Korea via period and cohort effects. Policies to reduce the growing burden of ID deaths should be further improved.

Functional expression and magnetic nanoparticle-based Immobilization of a protein-engineered marine fish epoxide hydrolase of Mugil cephalus for enantioselective hydrolysis of racemic styrene oxide.

A triple-point mutated fish microsomal epoxide hydrolase (mEH) gene from Mugil cephalus was expressed in Escherichia coli in the presence of various chaperones to prevent protein aggregations. The enantioselective hydrolytic activity was more than doubled by co-expressing the EH mutant gene with pGro7 plasmid. The highly active EH mutant with a his-tag was immobilized onto magnetic silica assembled with NiO nanoparticles. The immobilized mEH mutant was re-used more than 10 times with less than 10% activity loss. (S)-Styrene oxide with 98% enantiopurity was repeatedly obtained with over 50% of the theoretical yield by the magnetically separable high-performance mEH mutant.

[Effects of Oral Gargling with Aroma Solution in Psychiatric Inpatients: A Non-Randomized Controlled Trial].

PURPOSE: The purpose of this study was to examine the effects of oral gargling with an aromatic solution on xerostomia, objective oral status, and oral health-related quality of life in psychiatric inpatients. METHODS: A nonequivalent control group with a non-synchronized design was used in this study. The experimental group (n=34) received oral gargling with an aroma solution, while the control group (n=33) gargled with 0.9% normal saline. Dependent variables were measured at pre-, post-, and follow-up test. Data were analyzed using an χ²-test, Fisher's exact probability test, t-tests, and repeated measures ANOVA using SPSS/WIN v.21.0. RESULTS: After the intervention, significant differences were revealed in xerostomia (F=15.30, p <.001), objective oral status (F=38.44, p <.001), and oral health-related quality of life (F=62.70, p <.001) with an interaction effect between group and time. CONCLUSION: These findings indicate that gargling with an aroma solution is more effective than 0.9% normal saline for the oral health of psychiatric inpatients. Therefore gargling with an aroma can be safely recommended as a brief, economical, and positive intervention in clinical settings.