Multiple toll-like receptors (TLRs) display differential bacterial and ligand specificity in the earthworm, Eisenia andrei

Toll-like receptors (TLRs), an ancient and well-conserved group of pattern recognition receptors (PRRs), recognize conserved pathogen-associated molecular patterns. TLRs consist of three domains: the extracellular N-terminal domain, containing one or more leucine-rich repeats (LRRs), responsible for the recognizing and binding of antigens; the type-I transmembrane domain; and the intracellular domain known as the Toll/Interleukin-1 receptor (TIR) domain required for the downstream signaling pathway. We identified six new full-length complementary DNA (cDNA) sequences, Ean-TLR1/2/3/4/5/6. The deduced amino acid sequences indicate that Ean-TLRs consist of one signal peptide, one LRR N-terminal domain (Ean-TLR4/5), varying numbers of LRRs, one (Ean-TLR1/2/3/4/5) or two (Ean-TLR6) LRR C-terminal domains, one type-I transmembrane domain, and a TIR domain. In addition, a TIR domain alignment revealed that three conserved motifs, designated as Box 1, Box 2, and Box 3, contain essential amino acid residues for downstream signaling activity. Phylogenetic analysis of earthworm TLRs generated two separate evolutionary branches representing single (sccTLR) and multiple (mccTLR) cysteine cluster TLRs. Ean-TLR1/2/3/4 (sccTLR type) and Ean-TLR6 (mccTLR type) were clustered with corresponding types of previously reported earthworm TLRs as well as TLRs from Clitellata and Polychaete. As PRRs, earthworm TLRs should be capable of sensing a diverse range of pathogens. Except for Ean-TLR3, which was not responsive to any bacteria, earthworm TLR expression was significantly induced by Gram-positive but not Gram-negative bacteria. Moreover, it is likely that earthworms can differentiate between different species of Gram-positive bacteria via their TLR responses. The ligand specificity of earthworm TLRs suggests that their pathogenic ligand recognition is likely to be as specific and diverse as the mammalian TLR pathogen-sensing system.

Slit-Robo expression in the leech nervous system: insights into eyespot evolution

BACKGROUND

Slit and Robo are evolutionarily conserved ligand and receptor proteins, respectively, but the number of slit and robo gene paralogs varies across recent bilaterian genomes. Previous studies indicate that this ligand-receptor complex is involved in axon guidance. Given the lack of data regarding Slit/Robo in the Lophotrochozoa compared to Ecdysozoa and Deuterostomia, the present study aims to identify and characterize the expression of Slit/Robo orthologs in leech development.

RESULTS

We identified one slit (Hau-slit), and two robo genes (Hau-robo1 and Hau-robo2), and characterized their expression spatiotemporally during the development of the glossiphoniid leech Helobdella austinensis. Throughout segmentation and organogenesis, Hau-slit and Hau-robo1 are broadly expressed in complex and roughly complementary patterns in the ventral and dorsal midline, nerve ganglia, foregut, visceral mesoderm and/or endoderm of the crop, rectum and reproductive organs. Before yolk exhaustion, Hau-robo1 is also expressed where the pigmented eye spots will later develop, and Hau-slit is expressed in the area between these future eye spots. In contrast, Hau-robo2 expression is extremely limited, appearing first in the developing pigmented eye spots, and later in the three additional pairs of cryptic eye spots in head region that never develop pigment. Comparing the expression of robo orthologs between H. austinensis and another glossiphoniid leech, Alboglossiphonia lata allows to that robo1 and robo2 operate combinatorially to differentially specify pigmented and cryptic eyespots within the glossiphoniid leeches.

CONCLUSIONS

Our results support a conserved role in neurogenesis, midline formation and eye spot development for Slit/Robo in the Lophotrochozoa, and provide relevant data for evo-devo studies related to nervous system evolution.

Interaction-and-Response Network for Distantly Supervised Relation Extraction

Distantly supervised relation extraction (DSRE) aims to identify semantic relations from massive plain texts. A broad range of the prior research has leveraged a series of selective attention mechanisms over sentences in a bag to extract relation features without considering dependencies among the relation features. As a result, potential discriminative information existed in the dependencies is ignored, causing a decline in the performance of extracting entity relations. In this article, we focus on going beyond the selective attention mechanisms and propose a new framework termed interaction-and-response network (IR-Net) that adaptively recalibrates the features of sentence, bag, and group levels by explicitly modeling interdependencies among the features on each level. The IR-Net consists of a series of interactive and responsive modules throughout feature hierarchy, seeking to strengthen its power of learning salient discriminative features for distinguishing entity relations. We conduct extensive experiments on three benchmark DSRE datasets, including NYT-10, NYT-16, and Wiki-20m. The experimental results demonstrate that the IR-Net brings obvious improvements in performance when comparing ten state-of-the-art DSRE methods for entity relation extraction.

Peptidoglycan recognition proteins from the earthworm, Eisenia andrei: Differential inducibility and tissue-specific expression

Several pattern recognition receptors (PRRs) involved in innate immunity have been identified and characterized in earthworms. Peptidoglycan recognition proteins (PGRPs) are highly conserved PRRs that activate effector pathways such as prophenoloxidase cascade and Toll-like receptor pathway. In addition, PGRPs function as an enzyme, N-acetylmuramoyl-l-alanine amidase (NAMLAA), to directly hydrolyze peptidoglycan. We identified four full-length complementary DNA (cDNA) sequences, Ean-PGRP1/2/3/4, in Eisenia andrei, an earthworm. Sequence and phylogenetic analyses indicate that earthworm PGRP orthologs resemble short PGRP member proteins. The subcellular localizations of four Ean-PGRPs lacking the transmembrane domain are predicted to be extracellular or cytoplasmic. All Ean-PGRPs contain a highly conserved PGRP domain with a conserved Zn²⁺ binding site including a tyrosine residue essential for active amidase activity. Three highly conserved amino-acid residues (His, Trp, and Thr) necessary for amidase activity are also present, indicating that the Ean-PGRPs can be predicted to have amidase activity. Furthermore, we demonstrate that the Ean-PGRP genes are differentially induced by certain bacterial species, suggesting that the innate immune system of earthworms is likely to be somewhat specific rather than entirely non-specific. Tissue expression patterns indicate that Ean-PGRP mRNAs are primarily expressed in the immune-competent tissues and that their expression is tissue-specific according to Ean-PGRP types, particularly for Ean-PGRP1.

Head transcriptome profiling of glossiphoniid leech (Helobdella austinensis) reveals clues about proboscis development

Cephalization refers to the evolutionary trend towards the concentration of neural tissues, sensory organs, mouth and associated structures at the front end of bilaterian animals. Comprehensive studies on gene expression related to the anterior formation in invertebrate models are currently lacking. In this study, we performed de novo transcriptional profiling on a proboscis-bearing leech (Helobdella austinensis) to identify differentially expressed genes (DEGs) in the anterior versus other parts of the body, in particular to find clues as to the development of the proboscis. Between the head and the body, 132 head-specific DEGs were identified, of which we chose 11 to investigate their developmental function during embryogenesis. Analysis of the spatial expression of these genes using in situ hybridization showed that they were characteristically expressed in the anterior region of the developing embryo, including the proboscis. Our results provide information on the genes related to head formation and insights into the function of proboscis-related genes during organogenesis with the potential roles of genes not yet characterized.

Transcriptional upregulation of multiple earthworm chitinase genes following bacterial challenge suggests their implications in innate immunity

BACKGROUND

Chitinase is a multi-functional enzyme that catalyzes the hydrolysis of β-1,4-linkages between N-acetylglucosamines (GlcNAc) in chitin. Recent studies imply that earthworm chitinase is implicated in self-defense immunity against chitin-containing pathogens. However, a direct relationship of earthworm chitinase with innate immunity has not yet been established.

OBJECTIVE

In this study, earthworm (Eisenia andrei) chitinase expression was examined following bacterial challenge by Bacillus subtilis.

METHODS

RNA sequencing (RNA-seq) and real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) were used to quantitatively evaluate mRNA expression changes in response to bacterial stimulation.

RESULTS

Multiple chitinase-related mRNAs were found to be upregulated, among which EaChi3, EaChi4, and EaChi2 were upregulated by approximately eightfold, eightfold, and 2.5-fold, respectively. This strongly suggested that earthworm chitinases may act as inducible humoral effectors in earthworm innate immunity. The primary structures of all three chitinases contained an N-terminal glycol_18 domain with two chitin-binding and chitin-catalyzing domains, and a C-terminal proline, glycine, serine, threonine (PGST)-rich domain. In addition, EaChi2 had a chitin-binding peritrophin-A domain at the end of the C-terminus with 5 cysteine residues possibly contributing two intradomain disulfide bonds. Multiple sequence alignment of the catalytic domain centers of glycol_18 domain displayed highly conserved chitin-binding and chitin-catalyzing domains in which three essential amino acid residues (D, D, E) for catalyzing activity are well conserved except EaChi4. The critical glutamic acid (E) residue was substituted for glutamine (Q) in EaChi4 indicating that it is devoid of catalytic activity.

CONCLUSIONS

To our knowledge, this is the first report providing direct evidence that multiple earthworm chitinases are bacteria-responsive, strongly suggesting that earthworm chitinases are inducible humoral effectors in earthworm innate immunity. In addition, our results possibly suggest that earthworm EaChi4 may function as a pattern recognition molecule modulating the downstream immune pathway.

Identification and Spatiotemporal Expression of Adenosine Deaminases Acting on RNA (ADAR) during Earthworm Regeneration: Its Possible Implication in Muscle Redifferentiation

Simple Summary

Among the animal species capable of regenerating missing body parts, a species of earthworm, Perionyx excavatus, has the most powerful regeneration capacity, which can completely and regenerate an amputated head and tail. Earthworm regeneration is a form of epimorphosis, a simple mode of development in adults that occurs around the sites of damage rather than throughout the body. In order to achieve this process, the earthworm must have molecular tools via which a variety of cell and tissue types can be precisely recovered from the pluripotent (or possibly totipotent) blastemal cells. Adenosine to inosine (A-to-I) RNA editing catalyzed by adenosine deaminases acting on RNA (ADAR) can generate substantial transcriptome and proteome variability and provide an ideal tool for cell and tissue re-specification. To understand the role of ADAR during earthworm regeneration, the molecular characteristics of an ADAR gene identified from P. excavatus (Pex-ADAR) were analyzed, and its spatial and temporal expression patterns were observed during regeneration. Domain analysis showed that Pex-ADAR is a member of the ADAR1 class. Its expression level primarily increases when and where muscle redifferentiation is actively taking place, suggesting that the RNA-editing enzyme Pex-ADAR is involved in muscle redifferentiation.

Abstract

Adenosine deaminases acting on RNA (ADAR) catalyze the hydrolytic deamination of adenosine (A) to produce inosine (I) in double-stranded RNA substrates. A-to-I RNA editing has increasingly broad physiological significance in development, carcinogenesis, and environmental adaptation. Perionyx excavatus is an earthworm with potent regenerative potential; it can regenerate the head and tail and is an advantageous model system to investigate the molecular mechanisms of regeneration. During RNA sequencing analysis of P. excavatus regenerates, we identified an ADAR homolog (Pex-ADAR), which led us to examine its spatial and temporal expression to comprehend how Pex-ADAR is linked to regeneration. At first, in domain analysis, we discovered that Pex-ADAR only has one double-stranded RNA-binding domain (dsRBD) and a deaminase domain without a Z-DNA-binding domain (ZBD). In addition, a comparison of the core deaminase domains of Pex-ADAR with those of other ADAR family members indicated that Pex-ADAR comprises the conserved three active-site motifs and a glutamate residue for catalytic activity. Pex-ADAR also shares 11 conserved residues, a characteristic of ADAR1, supporting that Pex-ADAR is a member of ADAR1 class. Its temporal expression was remarkably low in the early stages of regeneration before suddenly increasing at 10 days post amputation (dpa) when diverse cell types and tissues were being regenerated. In situ hybridization of Pex-ADAR messenger RNA (mRNA) indicated that the main expression was observed in regenerating muscle layers and related connective tissues. Taken together, the present results demonstrate that an RNA-editing enzyme, Pex-ADAR, is implicated in muscle redifferentiation during earthworm regeneration.

Characterization of Perionyx excavatus Development and Its Head Regeneration

Regeneration is a biological process restoring lost or amputated body parts. The capability of regeneration varies among organisms and the regeneration of the central nervous system (CNS) is limited to specific animals, including the earthworm Perionyx excavatus. Thus, it is crucial to establish P. excavatus as a model system to investigate mechanisms of CNS regeneration. Here, we set up a culture system to sustain the life cycle of P. excavatus and characterize the development of P. excavatus, from embryo to juvenile, based on its morphology, myogenesis and neurogenesis. During development, embryos have EdU-positive proliferating cells throughout the whole body, whereas juveniles maintain proliferating cells exclusively in the head and tail regions, not in the trunk region. Interestingly, juveniles amputated at the trunk, which lacks proliferating cells, are able to regenerate the entire head. In this process, a group of cells, which are fully differentiated, reactivates cell proliferation. Our data suggest that P. excavatus is a model system to study CNS regeneration, which is dependent on the dedifferentiation of cells.

Long-term mortality of patients with tuberculosis in Korea

BACKGROUND: Long-term mortality following tuberculosis (TB) diagnosis in Korea remains unclear.METHODS: The present study used data from the National Health Insurance Service database, an extensive health-related database including most Korean residents. TB patients were identified using International Classification of Diseases, Tenth Revision coding (A15-19, U88.0-88.1) and the type of anti-TB drug(s) between 2003 and 2016. Long-term mortality and causes of death in TB patients were analysed.RESULTS: A total of 357 211 individuals had TB over the period from 2003 to 2016 and 103 682 died. The mean age of the cohort was 54.7 ± 20.7 years, and 59.8% were male. The survival probability of TB patients at 1, 5, and 10 years after diagnosis was 87.8%, 75.3%, and 63.3%, respectively. High mortality and TB-related death rates were especially prominent in the early stages after TB diagnosis. The overall standardized mortality ratio of TB patients to the general Korean population was 3.23 (95% confidence interval 3.21-3.25).CONCLUSION: Mortality in TB patients was especially high in the early stages of disease after TB diagnosis, and mostly due to TB. This figure was approximately three-times higher than the mortality rate in the general population.

Upregulation of cellulase activity and mRNA levels by bacterial challenge in the earthworm Eisenia andrei, supporting the involvement of cellulases in innate immunity

To investigate whether earthworm cellulases contribute to the innate immune system, the responsiveness of cellulase activity and mRNA expression to bacterial challenge was examined by zymography and RNA sequencing. A zymographic analysis revealed that the activity levels of earthworm cellulases were upregulated in response to either a bacterial (Bacillus subtilis or Escherichia coli) or LPS challenge. After the challenge, significant increases in cellulase 1 and cellulase 2 activity levels were observed within 8-16 and 16-24 h, respectively. In the coelomic fluid, both activities were significantly upregulated at 8 h post-injection with B. subtilis. Based on RNA sequencing, cellulase-related mRNAs encoding beta-1,4-endoglucanases were upregulated by 3-fold within 6 h after B. subtilis injection. Our results clearly demonstrated that earthworm cellulases are upregulated by bacterial challenge at the mRNA and protein levels. These results support the view that earthworm cellulases act as inducible humoral effectors of innate immunity against bacterial infection.

Spatiotemporal Expression of Anticoagulation Factor Antistasin in Freshwater Leeches

Antistasin, which was originally discovered in the salivary glands of the Mexican leech Haementeria officinalis, was newly isolated from Helobdella austinensis. To confirm the temporal expression of antistasin during embryogenesis, we carried out semi-quantitative RT-PCR. Hau-antistasin1 was uniquely expressed at stage 4 of the cleavage and was strongly expressed in the late stages of organogenesis, as were other antistasin members. In order to confirm the spatial expression of antistasin, we performed fluorescence in situ hybridization in the late stages of organogenesis. The expression of each antistasin in the proboscis showed a similar pattern and varied in expression in the body. In addition, the spatial expression of antistasin orthologs in different leeches showed the possibility of different function across leech species. Hau-antistasin1 was expressed in the same region as hedgehog, which is a known mediator of signal transduction pathway. Hau-antistasin1 is probably a downstream target of Hedgehog signaling, involved in segment polarity signal pathway.

Antioxidant, antibacterial, and anti-adhesive activities of biosurfactants isolated from Bacillus strains

Biosurfactants are surface-active compounds that display a range of physiological functions. The present study investigated the antioxidant, antimicrobial, and anti-adhesive or anti-biofilm potential of biosurfactants isolated from Bacillus subtilis VSG4 and Bacillus licheniformis VS16. The antioxidant activity of the biosurfactants was studied in vitro using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radicals. At 5 mg/mL of the biosurfactant concentration, the scavenging of DPPH and hydroxyl radicals was found to be between 69.1-73.5% and 63.3-69.8%, respectively. The biosurfactants also displayed significant antibacterial activities against both Gram-positive and Gram-negative bacteria. The anti-adhesive activities of the biosurfactants were evaluated against Staphylococcus aureus ATCC 29523, Salmonella typhimurium ATCC 19430, and Bacillus cereus ATCC 11778. The biosurfactants exhibited anti-adhesive activity, even at concentrations of 3-5 mg/mL. Moreover, both biosurfactants displayed notable anti-biofilm activities with a biofilm eradication percentage ranging from 63.9 to 80.03% for VSG4 biosurfactant, and from 61.1-68.4% for VS16 biosurfactant. Furthermore, VSG4 biosurfactant exhibited emulsification and surface tension stability over a wide range of pH (4-10) and temperature up to 100 °C. These results show that VSG4 and VS16 biosurfactants can be potentially used as natural antioxidants, antimicrobials, and/or anti-adhesive agents for food and biomedical applications.

Analysis of Pre-transplant Resuscitation Factors Influencing Immediate Graft Function After Deceased Donor Kidney Transplantation

BACKGROUND

The management of a deceased donor in the intensive care unit before organ transplantation is important for the outcome of the recipient. Herein, we analyze the pre-transplant resuscitation factors managed before procurement that could influence graft function immediately after deceased-donor kidney transplantation (DDKT).

METHODS

A total of 271 DDKTs performed at Seoul St. Mary's Hospital, Korea, from January 2009 to March 2016 were reviewed. We divided the patients into a delayed graft function (DGF) group and a non-DGF group, and compared postoperative outcomes between the 2 groups. We also analyzed the predisposing factors of DGF using multivariate analysis.

RESULTS

A total of 36 cases developed DGF while 235 patients did not, and the demographic characteristics of the recipients in the two groups had no significant difference. Of the pre-transplant resuscitation factors, preoperative polyuria, the maximal levels of serum sodium and BUN, and transfer times were significantly higher in the DGF group (P < .001). In a multivariable analysis, preoperative polyuria (odds ratio 4.835, P = .036), elevated preoperative level of sodium (odds ratio 1.227, P = .001), and extended transfer times (odds ratio 1.001, P < .001) were the independent risk factors of the donor in pre-transplant resuscitation management associated with DGF.

CONCLUSIONS

Polyuria, high levels of sodium before procurement, and prolonged transfer times are independent risk factors for DGF after a DDKT. Active intervention and early implementation of the intensivist can help in managing these factors effectively and thus ultimately improve graft function.

Temporal and spatial expression of the Fox gene family in the Leech Helobdella austinensis

The Forkhead box (Fox) gene family is an evolutionarily ancient gene family named after the Drosophila melanogaster forkhead gene (fkh). Fox genes are highly conserved transcription factors critical for embryogenesis and carcinogenesis. In the current study, we report a whole-genome survey of Fox genes and their expression patterns in the leech Helobdella austienesis. Phylogenetic analysis suggests that some Fox genes of leeches are correlated with other Lophotrochozoa and vertebrate Fox genes. Here we have performed semiquantitative reverse transcription polymerase chain reaction and whole-mount in situ hybridization of Fox genes throughout the embryonic development of H. austinensis. We found that each one of the leech Fox genes (FoxA1, FoxA3, FoxC, FoxL2, FoxO1, and FoxO2) is expressed in a specific set of cells or tissue type. From Stages 9-11, Hau-FoxA1 was expressed in the foregut of the anterior region, and Hau-FoxL2 was expressed in mesodermal muscle fiber. Hau-FoxA3 was temporally expressed in the ventral neuroectoderm. At Stage 11, Hau-FoxC was expressed in the foregut. Hau-FoxO genes have a ubiquitous expression. Our results provide more insight on the evolutionary linkage and role of the Fox gene function in Bilateria.

Kidney Transplantation Using Expanded-Criteria Deceased Donors: A Comparison With Ideal Deceased Donors and Non-Expanded-Criteria Deceased Donors

PURPOSE

The use of expanded-criteria deceased-donor (ECD) kidneys must be evaluated within the objective perspective of critical organ shortage and graft function and survival. In this study, we aimed to compare the clinical outcomes of ECD reliance with concurrent use of ideal-criteria deceased donors (IDDs) and non-ECDs in adult renal transplantation.

METHODS

Between February 2000 and December 2015, we analyzed 405 deceased-donor renal transplants, specifically 129 grafts (31.9%) from ECDs, 233 grafts (57.5%) from non-ECDs, and 43 grafts (10.6%) from IDDs. ECDs were classified according to the United Network for Organ Sharing guidelines, while an IDD was defined as a younger person (10-39 years of age) with no medical risk factors who died from a traumatic head injury. Donor and recipient risk factors were separately analyzed and correlated with recipient graft function, and survival was evaluated.

RESULTS

ECDs were older (56.8 ± 6.3 years); showed increased incidence of hypertension, diabetes, and cerebrovascular brain death; and had a higher pre-retrieval serum creatinine level than the other groups. ECD kidney recipients were also older (50.6 ± 9.8 years), had a shorter waiting time (P = .031), and demonstrated a low frequency of re-transplantation (P = .028). Long-term renal function followed longitudinally was lower in ECD kidney recipients until five years after transplantation, while the glomerular filtration rate (GFR) level at 7 and 10 years did not differ significantly among the groups (P = .074 and .262, respectively). There were no significant differences in terms of graft survival (P = .394) or patient survival (P = .737) among the groups.

CONCLUSIONS

Although the long-term renal function followed longitudinally was lower in ECD kidney recipients, the use of renal grafts from ECDs is an acceptable method to resolve the disparity of critical organ shortage. However, the classification of the high-risk group should be updated with consideration given to differences in regional characteristics.

First report of carp oedema virus infection of koi (Cyprinus carpio haematopterus) in the Republic of Korea

Twenty-five koi (Cyprinus carpio haematopterus) bought from a wholesale fish market in Korea, showed lethargic behaviour and 100% mortality within 20 days. Carp oedema virus (CEV) was detected by PCR in all 25 koi. Results of detailed histopathological and clinical examinations of 17 koi indicated loss of body balance, severe infiltration of inflammatory cells into the inter-lamellar spaces of the gills and vacuolization and inclusion bodies in gill epithelial cells. Sequence analysis of PCR products of these koi showed up to 99% identity to the previously reported sequences, suggesting that the observed mass mortality resulted from koi sleepy disease (KSD) due to CEV infection. To the best of our knowledge, this study is the first report of KSD in the Republic of Korea. Partial sequences of 4a protein from the virus indicated that the present CEV detected in koi from Korea is more closely related to that from the UK and Poland than from Japan. The present findings indicate that the prevalence and spread of KSD must be closely monitored in both European and Asian countries to avoid potential economic losses to the global koi industry.

The association between season of birth, age at onset, and clozapine use in schizophrenia

OBJECTIVE

This study aimed to determine whether the rate of clozapine use, an indicator of refractoriness in schizophrenia, is associated with the season of birth and age at onset in patients with schizophrenia based on nationwide data.

METHODS

Patients with schizophrenia (n = 114 749) who received prescriptions for antipsychotic medication between 2008 and 2014 were retrospectively identified from the Korean National Health Insurance Service database. The study population was divided into three groups based on their age at the onset of schizophrenia (early, middle, and late onset). We assessed differences in the month of birth between patients and the general population. In addition, the cumulative clozapine use was calculated.

RESULTS

Compared to the late-onset schizophrenia group, the early- and middle-onset groups showed a higher probability of birth during the winter season. In addition, the early-onset group showed the highest cumulative clozapine use rate. In the middle-onset group, the initiation of clozapine use was significantly earlier for patients born in winter compared to those born in summer.

CONCLUSION

Our results indicate that the age at onset is an important factor in predicting the prognosis of schizophrenia patients. The season of birth also affects the prognosis, but with less robustness. Specifically, it appears that early disease onset and winter birth might be associated with poor outcomes in Korean patients with schizophrenia.

Triazolium cyclodextrin click cluster-resin conjugate: an enrichment material for phosphatidylinositol (3,4,5)-triphosphate

UltraLink was functionalized with a triazolium cyclodextrin click cluster (CCC) which provides a well-oriented, multivalent, positively charged binding site for PtdIns(3,4,5)P₃. MALDI TOF MS and LC ESI MS/MS MRM analysis of spiked PtdIns(3,4,5)P₃ in lipid extract suggest that triazolium CCC-UltraLink conjugate can be used as an enrichment material for PtdIns(3,4,5)P₃.

Spatiotemporal expression of a twist homolog in the leech Helobdella austinensis

Genes of the twist family encode bHLH transcription factors known to be involved in the regulation and differentiation of early mesoderm. Here, we report our characterization of Hau-twist, a twist homolog from the leech Helobdella austinensis, a tractable lophotrochozoan representative. Hau-twist was expressed in segmental founder cells of the mesodermal lineage, in subsets of cells within the mesodermal lineage of the germinal plate, in circumferential muscle fibers of a provisional integument during segmentation and organogenesis stages and on the ventral side of the developing proboscis. Thus, consistent with other systems, our results suggest that twist gene of the leech Helobdella might function in mesoderm differentiation.

A new earthworm cellulase and its possible role in the innate immunity

A new endogenous cellulase (Ean-EG) from the earthworm, Eisenia andrei and its expression pattern are demonstrated. Based on a deduced amino acid sequence, the open reading frame (ORF) of Ean-EG consisted of 1368 bps corresponding to a polypeptide of 456 amino acid residues in which is contained the conserved region specific to GHF9 that has the essential amino acid residues for enzyme activity. In multiple alignments and phylogenetic analysis, the deduced amino acid sequence of Ean- EG showed the highest sequence similarity (about 79%) to that of an annelid (Pheretima hilgendorfi) and could be clustered together with other GHF9 cellulases, indicating that Ean-EG could be categorized as a member of the GHF9 to which most animal cellulases belong. The histological expression pattern of Ean-EG mRNA using in situ hybridization revealed that the most distinct expression was observed in epithelial cells with positive hybridization signal in epidermis, chloragogen tissue cells, coelomic cell-aggregate, and even blood vessel, which could strongly support the fact that at least in the earthworm, Eisenia andrei, cellulase function must not be limited to digestive process but be possibly extended to the innate immunity.

4-n-butylresorcinol enhances proteolytic degradation of tyrosinase in B16F10 melanoma cells

OBJECTIVE

4-n-butylresorcinol is a competitive inhibitor of tyrosinase and has been used as an antimelanogenic agent. However, its inhibition mechanism in intact cells is not fully understood. To elucidate the cellular mechanism, we compared in vitro and in vivo inhibitory effects of 4-n-butylresorcinol on tyrosinase activity.

METHODS

B16F10 melanoma cells were cultured in media containing α-MSH in the presence or absence of 4-n-butylresorcinol. Tyrosinase mRNA levels, protein levels and activity in B16F10 cells were compared by real-time PCR, immunostaining combined with western blot and colorimetric analysis, respectively. Melanin concentration was measured by colorimetry both in the cells and in the media. Tyrosinase glycosylation and proteolytic degradation were analysed by immunoblotting after cells were treated with Endo H/PNGase F and E64/proteasome inhibitors, respectively.

RESULTS

4-n-butylresorcinol inhibited tyrosinase activity and melanin synthesis more effectively in intact cells than in cell lysates. Western blotting and real-time RT-PCR showed that 4-n-butylresorcinol reduced protein levels, but not mRNA levels, of tyrosinase in B16F10 cells. 4-n-butylresorcinol showed no effect on the processing of tyrosinase glycosylation or on trafficking to melanosomes. However, treatment of B16F10 cells with E64 or proteasome inhibitor abrogated the 4-n-butylresorcinol-induced decrease of tyrosinase. Moreover, 4-n-butylresorcinol activated p38 MAPK, resulting in increased ubiquitination of tyrosinase.

CONCLUSION

4-n-butylresorcinol inhibits melanogenesis by enhancing proteolytic degradation of tyrosinase as well as competitive binding to tyrosinase. These findings will help to develop new, effective and safe chemicals for the treatment of hyperpigmentation disorders.

Long-term outcomes of locally or radically resected T1 colorectal cancer

AIM

Little is known about the long-term outcome of T1 colorectal cancer (CRC) following curative resection. The present study addressed the long-term outcome of locally or radically resected T1 CRCs.

METHOD

A total of 430 patients with T1 CRC who underwent local or radical resection were considered. Unfavourable histological factors were defined as positive resection margin, deep submucosal invasion, vascular invasion, Grade 3 and budding. The patients were classified as low-risk (unfavourable histological factor negative, n = 65) or high-risk (unfavourable histological factor positive, n = 365).

RESULTS

Over a median follow-up of 78.4 months, disease recurred in 16 (3.7%) patients in the high-risk group, and no recurrence in the low-risk group. Resection type and vascular invasion were significantly associated with recurrence. In the vascular invasion (+) high-risk group, both 5-year disease-free survival rate and 5-year overall survival rate were significantly associated with resection type (radical 94.6%, local 43.8%, P < 0.001, and radical 99.1%, local 66.7%, P < 0.001). In the vascular invasion (-) high-risk group, 5-year disease-free survival rate was also significantly associated with resection type (radical 98.9%, local 84.7%, P = 0.001). However, 5-year overall survival rate was not associated with resection type (radical 98.9%, local 95.2%, P = 0.816).

CONCLUSION

Local resection may be effective and oncologically safe in low-risk T1 CRC. Although additional surgery should be recommended for the locally resected high-risk T1 CRC cases, intensive surveillance without additional surgery and timely salvage operation may offer another treatment option, if vascular invasion is negative.

The prevalence of causative organisms of community-acquired urethritis in an age group at high risk for sexually transmitted infections in Korean Soldiers

OBJECTIVES

This study was designed to evaluate the causative organisms in young male soldiers with clinical signs and symptoms after sexual contact that suggests a diagnosis of urethritis.

METHODS

Between June 2012 and January 2015, male patients with urethritis symptoms that had resulted from sexual contact within 3 months participated in this study. All patients were evaluated using urinalysis and were screened for Neisseria gonorrhoeae (NG), Chlamydia trachomatis (CT), Ureaplasma urealyticum (UU), Mycoplasma genitalium (MG), Mycoplasma hominis (MH), herpes simplex virus (HSV) type II and Trichomonas vaginalis (TV) using multiplex PCR (mPCR) assay in order to detect sexually transmitted infections (STI) or pathogens.

RESULTS

A total of 436 male patients aged 18-28 years were included in the study. The median age was 22.0 years. The prevalence of STI pathogens were as follows: NG in 19.0%, CT in 36.6%, UU in 24.0%, MG in 21.5%, MH in 6.1%, HSV type II in 1.6%, TV in 0.2% and indeterminate STI pathogens in 9.4%. Coinfection of NG with non-NG was detected in 5.7% of the participants, while the coinfection rates for STI pathogens were: with CT in 3.4%, with UU in 2.7%, with MG in 0.2% and with MH in 0.2%.

CONCLUSIONS

CT was the most prevalent STI pathogen and coinfections of NG with non-NG appeared less frequently. The young male soldiers with urethritis should be administered suitable antibiotics for STI pathogens that were found by mPCR results, rather than an experimental combination of antibiotics for coinfections.

Gene expression profiling of coelomic cells and discovery of immune-related genes in the earthworm, Eisenia andrei, using expressed sequence tags

The coelomic cells of the earthworm consist of leukocytes, chlorogocytes, and coelomocytes, which play an important role in innate immunity reactions. To gain insight into the expression profiles of coelomic cells of the earthworm, Eisenia andrei, we analyzed 1151 expressed sequence tags (ESTs) derived from the cDNA library of the coelomic cells. Among the 1151 ESTs analyzed, 493 ESTs (42.8%) showed a significant similarity to known genes and represented 164 unique genes, of which 93 ESTs were singletons and 71 ESTs manifested as two or more ESTs. From the 164 unique genes sequenced, we found 24 immune-related and cell defense genes. Furthermore, real-time PCR analysis showed that levels of lysenin-related proteins mRNA in coelomic cells of E. andrei were upregulated after the injection of Bacillus subtilis bacteria. This EST data-set would provide a valuable resource for future researches of earthworm immune system.

The early protective effect of glutamine pretreatment and ischemia preconditioning in renal ischemia-reperfusion injury of rat

BACKGROUND

Heat shock proteins (HSP) play an important role in protecting cells against stress.

METHODS

Using a rat model, we tested the hypothesis that pretreatment with glutamine (Gln) and ischemia preconditioning (IPC) increase the expression of HSP resulting in attenuation of renal ischemia/reperfusion (I/R) injury. Sprague-Dawley rats were randomized into 4 groups [group I, Gln injection (+), IPC (+); group II, Gln injection (+), IPC (-); group III, saline injection (+), IPC (+); group IV, saline injection (+), IPC (-)]. Renal HSP70 expression was determined by Western blotting and kidney function was assessed by blood urea nitrogen and serum creatinine. Renal cross-sections were microscopically examined for tubular necrosis, exfoliation of tubular epithelial cells, cast formation, and monocyte infiltration.

RESULTS

Gln pretreatment increased intrarenal HSP expression (P = .031). In group I, tubulointerstitial abnormalities were clearly slighter compared with the other groups (P < .001).

CONCLUSION

Our experiments suggest that (1) a single dose of Gln could induce HSP expression and (2) IPC could relieve renal I/R injury. In addition, IPC combined with Gln pretreatment had a synergic protective effect against renal I/R injury.

Contrast-enhanced magnetic resonance angiography in the early period after kidney transplantation

Our objective was to evaluate the usefulness of three-dimensional (3-D) contrast-enhanced (CE) magnetic resonance angiography (MRA) to assess renal parenchyma, arterial inflow stenosis, and peritransplant fluid collections in the early period after kidney transplantation (KT). Between January 2010 and April 2011, we examined a consecutive series of 144 renal transplants using 3-D CE MRA at 14 days after KT. MRA showed parenchyma infarctions (n = 17, 11.8%), arterial inflow stenoses (n = 23, 16%), lymphoceles (n = 14, 9.7%), and hematomas (n = 6, 4.2%). The degree of renal transplant artery inflow stenosis was graded qualitatively based on diameter criterion; <50% = mild, 50% to 70% = moderate, and >70% = severe in 10 (6.9%), 5 (3.5%), and 8 (5.6%) subjects, respectively. The study recipients were divided into 3 groups according to the degree of renal artery inflow stenosis (group I: normal; group II: mild and moderate, <70%; group III: severe, >70%). Among group III patients who underwent digital subtraction angiography, 5 had percutaneous transluminal angioplasty or stenting performed after 1 month. Their mean resume creatinine levels at 1, 6, and 12 months after transplantation were not significantly different from those in the other groups (P = .391, .447, .110). The prevalence of graft loss (n = 2) was high in group III (P = .012), although the frequency of acute rejection episodes was not different among the groups (P = .890). The incidences of renal parenchyma infarction, peritransplant fluid collection and arterial inflow stenosis were unexpectedly high in the early period after KT. Thus, 3-D CE MRA provided a rapid global assessment of the renal parenchyma, transplant arterial system, and peritransplant fluid collection that can be helpful to detect or exclude many causes of renal transplant dysfunction.

The natural history of arteriovenous access and risk factors associated with access thrombosis after successful kidney transplantation

INTRODUCTION

The purpose of this study was to determine the natural history of arteriovenous (AV) access after successful kidney transplantation (KT) and to identify the risk factors of spontaneous access closure in kidney transplant recipients.

METHODS

We performed a retrospective review of 115 patients who underwent KT with functioning access from June 2010 to July 2012. AV access patency was checked and recorded daily during the hospital stay and at every visit to the outpatient clinic. Patients were divided into 2 groups according to the patency of access, and risk factors of access thrombosis were assessed. Access patency was followed up until patency was lost or the study was closed.

RESULTS

At the end of follow-up, 18 (15.7%) AV accesses had spontaneously closed. Mean time to closure was 119 ± 163 days, and 12 of 18 were closed within 90 days after KT. AV access spontaneously closed in 8.5% of male patients, compared with 27.3% of female patients (P = .007), 12.2% of cases with native access compared with 35.3% of cases with artificial access (P = .016), and 11.3% of cases with wrist access compared with 25.7% of cases with elbow access (P = .049). Spontaneously closed AV accesses tended to have a lower mean access flow compared with functioning accesses (P = .019). On multivariate analysis, female sex and AV access flow volume affected spontaneous AV access closure (odds ratio 4.749, 95% confidence interval 1.919-35.383, P = .008; odds ratio 0.998, 95% confidence interval 0.996-0.999, P = .010, respectively).

CONCLUSIONS

Our results suggest that AV access thrombosis occurs more frequently during the early postoperative period, particularly in female patients or patients with low flow access, whereas it is a rare event in male patients or patients with high access flow, especially in the late postoperative period.

Validation of a scoring tool to predict drug-resistant pathogens in hospitalised pneumonia patients

BACKGROUND

Health care-associated pneumonia (HCAP) affects a heterogeneous group of patients in frequent contact with health care systems. However, HCAP criteria poorly predict infection with drug-resistant (DR) pathogens.

OBJECTIVE

To validate our previously reported risk-scoring model (predictive of DR pathogen infection) in patients admitted to hospital with pneumonia.

DESIGN

We evaluated 580 patients admitted with culture-positive bacterial pneumonia. We identified risk factors, evaluated the risk-scoring model's capacity to predict infection by DR pathogens and compared the model's diagnostic accuracy with that of current HCAP criteria.

RESULTS

DR pathogens were observed in 227/580 patients (39.1%). Of 269 HCAP patients, 153 (56.9%) were infected with DR pathogens. Overtreatment was more common in HCAP than in community-acquired pneumonia (58.7% vs. 41.2%, P < 0.001). Recent hospitalisation, admission from a long-term care facility, recent antibiotic treatment and tube feeding were independently associated with DR pathogens. For pathogen prediction, the risk-scoring model showed better diagnostic accuracy than HCAP criteria (area under receiver operating-characteristic curve = 0.723 vs. 0.673, P < 0.001).

CONCLUSION

According to current HCAP criteria, half of the HCAP patients were treated unnecessarily with broad-spectrum antibiotics. Risk scoring by stratifying risk factors could improve the identification of patients likely to be infected with DR pathogens.

Isolation and characterization of a lytic Myoviridae bacteriophage PAS-1 with broad infectivity in Aeromonas salmonicida

To search for candidate control agents against Aeromonas salmonicida subsp. salmonicida infections in aquaculture, one bacteriophage (phage), designated as PAS-1, was isolated from the sediment samples of the rainbow trout (Oncorhynchus mykiss) culture farm in Korea. The PAS-1 was morphologically classified as Myoviridae and possessed approximately 48 kb of double-strand genomic DNA. The phage showed broad host ranges to other subspecies of A. salmonicida as well as A. salmonicida subsp. salmonicida including antibiotic-resistant strains. Its latent period and burst size were estimated to be approximately 40 min and 116.7 PFU/cell, respectively. Furthermore, genomic and structural proteomic analysis of PAS-1 revealed that the phage was closely related to other Myoviridae phages infecting enterobacteria or Aeromonas species. The bacteriolytic activity of phage PAS-1 was evaluated using three subspecies of A. salmonicida strain at different doses of multiplicity of infection, and the results proved to be efficient for the reduction of bacterial growth. Based on these results, PAS-1 could be considered as a novel Aeromonas phage and might have potentiality to reduce the impacts of A. salmonicida infections in aquaculture.

Predictors for lymph node metastasis in T1 colorectal cancer

BACKGROUND AND STUDY AIMS

It is critical that the risk of lymph node metastasis (LNM) is evaluated for determining the suitability of endoscopic resection for T1 colorectal cancer (CRC). Reported risk factors for LNM in completely resected T1 CRC are deep submucosal invasion, grade 3, angiolymphatic invasion, and budding. The aim of the present study was to identify the histopathologic factors associated with LNM in T1 CRC.

PATIENTS AND METHODS

The study involved 435 patients with T1 CRC treated by endoscopic or surgical resection between January 2001 and April 2010 at the National Cancer Center, Korea. The 435 patients were classified into two groups - those undergoing surgical resection (n = 324) and those undergoing endoscopic resection (n = 111). In the surgically resected group, details regarding depth of submucosal invasion, angiolymphatic invasion, tumor grade, budding, and background adenoma (BGA) were evaluated with respect to presence or absence of LNM. In the endoscopically resected group, the results of follow-ups and additional salvage surgeries were studied.

RESULTS

In the surgically resected group, LNM was detected in 42 patients (13.0 %). Grade 3, angiolymphatic invasion, budding, and the absence of BGA were identified as factors associated with LNM in univariate and multivariate analyses (P < 0.05). Among the 50 patients in the endoscopically resected group with high risk, three were diagnosed as being LNM-positive during the follow-up period. There was no LNM in the endoscopically resected group with low risk.

CONCLUSIONS

Grade 3, angiolymphatic invasion, budding, and the absence of BGA are the risk factors that predict LNM in patients with T1 CRC. In cases where endoscopically resected T1 CRC has no risk factor, cautious follow-up could be recommended. However, if the tumor has any risk factor, additional surgical resection should be considered.

Does donor kidney to recipient body weight ratio influence long-term outcomes of living-donor kidney transplantation?

This study evaluated the effect of the donor kidney to recipient body weight (Kw/Rw) ratio on long-term graft function and survival. We investigated retrospectively whether there was any association between Kw/Rw ratio and long-term graft survival and function after a follow-up of >10 years. We studied a consecutive series of 123 adult-to-adult living kidney transplants. According to the Kw/Rw ratio, patients were divided into 3 groups: "low" (Kw/Rw <2.85; n = 29), "medium" (2.85 ≤ Kw/Rw < 4.04; n = 63), and "high" (≥4.04; n = 31). Among the 3 groups, the mean serum creatinine levels at 1 and 6 months as well as 1 year after transplantation were significantly lower among patients with a high Kw/Rw ratio than in those with a medium or low ratio, but serum creatinine levels at 3 and 5 years did not differ significantly (P = .394 and 0.620, respectively). Graft survival rates at 5 and 10 years after transplantation were significantly lower in the "low" group. We observed a significant association between Kw/Rw ratio and graft survival (P = .018). The Kw/Rw ratio is an important factor for long-term graft survival and early graft function. However, it did not significantly affect subsequent renal function.

Lymph node ratio is an independent prognostic factor in patients with rectal cancer treated with preoperative chemoradiotherapy and curative resection

PURPOSE

To evaluate the prognostic effect of lymph node ratio (LNR) in patients with locally advanced rectal cancer who were treated with curative resection after preoperative chemoradiotherapy (CRT).

METHODS

Between October 2001 and December 2007, 519 patients who had undergone curative resection of primary rectal cancer after preoperative CRT were enrolled. Of these, 154 patients were positive for lymph node (LN) metastasis and were divided into three groups according to the LNR (≤ 0.15 [n=80], 0.16-0.3 [n=44], >0.3 [n=30]) to evaluate the prognostic effect on overall survival (OS) and disease-free survival (DFS).

RESULTS

LNR (≤ 0.15, 0.16-0.3, and >0.3) was significantly associated with 5-year OS (90.3%, 75.1%, and 45.1%; p<0.001) and DFS (66.7%, 55.8%, and 21.9%; p<0.001) rates. In a multivariate analysis, LNR (≤ 0.15, 0.16-0.3, and >0.3) was a significant independent prognostic factor for OS (hazard ratios [HRs], 1, 3.609, and 8.197; p<0.001) and DFS (HRs, 1, 1.699, and 3.960; p<0.001). LNR had a prognostic impact on OS and DFS in patients with <12 harvested LNs, as well as in those with ≥ 12 harvested LNs (p<0.05).

CONCLUSION

LNR was a significant independent prognostic predictor for OS and DFS in patients with locally advanced rectal cancer who were treated with curative resection after preoperative CRT.

Gene expression profiling of a cold-shocked earthworm Eisenia andrei

To identify genes that are modulated under cold-stress conditions in the earthworm Eisenia andrei, we performed a genome-wide analysis of gene expression in cold-shocked earthworms by using Serial Analysis of Gene Expression (SAGE). We identified 5,977 and 5,407 unique SAGE tags under normal and cold-stressed conditions, respectively. The majority of the SAGE tags did not match to any known expressed sequences, due to a paucity of expression data in earthworms. We converted the statistically significant SAGE tags for the cold-stressed condition into expressed sequence tags (ESTs), and the results showed that particular genes associated with energy homeostasis, cellular defense mechanisms, and ion balance were up-regulated or down-regulated. We constructed a regulatory network of some of these genes and identified rps-6 as a core gene in the cold-response regulatory-gene network. Our data provide a baseline for gene expression studies of cold shock in the Lumbricidae.

Genomic sequence of infectious hypodermal and hematopoietic necrosis virus (IHHNV) KLV-2010-01 originating from the first Korean outbreak in cultured Litopenaeus vannamei

Due to the need to track and monitor genetic diversity, the genome of the infectious hypodermal and hematopoietic necrosis virus (IHHNV) strain KLV-2010-01 in cultured Litopenaeus vannamei shrimp that originated from the first Korean outbreak in 2010 was sequenced and analyzed. The genome, with a length of 3914 nucleotides, was sequenced from the Korean IHHNV. The genome encoded three large and overlapping open reading frames: ORF1 (NS-1) of 2001 bp, ORF2 (NS-2) of 1092 bp and ORF3 (capsid protein) of 990 bp. The overall organization, size and predicted amino acid sequence of the three ORFs in Korean IHHNV were highly similar to those of members of the infectious IHHNV group, and the most closely related strains were IHHNVs described from Ecuador and Hawaii. Additionally, phylogenetic analysis showed that the Korean IHHNV was clustered with lineage III in the infectious IHHNV group and was most similar to IHHNV isolates from Ecuador, China and Taiwan.

Prevalence and different characteristics of two serotypes of Streptococcus parauberis isolated from the farmed olive flounder, Paralichthys olivaceus (Temminck and Schlegel), in Korea

The prevalence of two serotypes of Streptococcus parauberis isolated from the olive flounder, Paralichthys olivaceus, was evaluated in a total of 29 isolates between 2003 and 2010 in Korea. Streptococcus parauberis isolates were divided into two serologically distinct types (serotype 1 and serotype 2), except for one strain (S1091), using an agglutination assay with rabbit antiserum, and serotype 1 was identified as the dominant type (24 of 29 isolates) in this study. To identify the characteristics of the two serotypes of S. parauberis, we conducted a biochemical test using the API 20 Strep kit, a transmission electron microscopy (TEM) assay, sequence analysis of 16S-23S rRNA intergenic spacer region (ISR) and a pathogenicity test. In TEM, both serotypes possessed polysaccharide capsule layers around the cell surface when bacterial cells were treated with a homologous serotype of rabbit antiserum. However, we were unable to discriminate serotype-specific biochemical characteristics and genetic characteristics of 16S-23S rRNA ISR between the two serotypes. In the pathogenicity test, the serotype 1 strains induced significantly higher mortality than the serotype 2 strains in olive flounder when experimentally inoculated via the intraperitoneal route.

Effect of dimethyl sulfoxide on cell cycle synchronization of goldfish caudal fin derived fibroblasts cells

Several studies have previously been conducted regarding cell cycle synchronization in mammalian somatic cells. However, limited work has been performed on the control of cell cycle stages in the somatic cells of fish. The aim of this study was to determine the cell cycle arresting effects of several dimethyl sulfoxide (DMSO) concentrations for different times on different cell cycle stages of goldfish caudal fin-derived fibroblasts. Results demonstrated that the cycling cells or control group (68.29%) yields significantly higher (p < 0.05) arrest in G0/G1 phase compared with the group treated for 24 h with different concentrations (0.5%, 1.0% or 1.5%) of DMSO (64.88%, 65.70%, 64.22% respectively). The cell cycle synchronization in the treatment of cells with 1.0% DMSO at 48 h (81.14%) was significantly higher than that in the groups treated for 24 h (76.82%) and the control group (77.90%). Observations showed that treatment of DMSO resulted in an increase in the proportion of cells at G0/G1 phase for 48 h of culture. However, high levels of apoptotic cells can be detected after 48 h of culture treated with 1% concentration of DMSO.

Antimicrobial activity of the constituents of Smallanthus sonchifolius leaves against methicillin-resistant Staphylococcus aureus

BACKGROUND AND OBJECTIVES

Methicillin-resistant Staphylococcus aureus (MRSA) has been a serious problem as its infection is associated with higher mortality and increase cost worldwide. In the present study, the antibacterial activity of enhydrin, polymatin B, allo-schkuhriolide from the leaves of Smallanthus sonchifolius was investigated.

MATERIAL AND METHODS

Enhydrin, polymatin B, allo-schkuhriolide from the leaves of Smallanthus sonchifolius were tested for antimicrobial activity using micro dilution broth method against 2 strains of ATCC 33591, ATCC 25923 and 15 strains of clinical isolates MRSA.

RESULTS

The antibacterial activity of Smallanthus sonchifolius can safely be attributed to enhydrin as polymatin B, and allo-schkuhriolide are not showing any activity against Staphylococcus aureus strains. The enhydrin showed good antibacterial activity against all tested strains (MIC = 125-500 microg/ml).

DISCUSSION

These results suggest that only enhydrin can be considered as an antibacterial drug against MRSA.

Effect of probiotic-, bacteriophage-, or organic acid-supplemented feeds or fermented soybean meal on the growth performance, acute-phase response, and bacterial shedding of grower pigs challenged with Salmonella enterica serotype Typhimurium

A 28-d experiment evaluated the growth performance, acute-phase response, and bacterial shedding patterns in pigs (n = 108; initially, 38.7 ± 6.7 kg) fed 6 treatment diets, including a control diet with no antimicrobial agents (CON), a positive control diet containing chlortetracycline, 100 mg/kg (CT), a diet containing anti-Salmonella Typhimurium bacteriophage, 3 × 10(9) plaque-forming units/kg of feed (ASB), Lactobacillus plantarum CJLP56, 6.5 × 10(8) cfu/kg of feed (LP), 0.2% microencapsulated organic acids (MOA), or 5% fermented soybean meal (FSM). Pigs were fed the diets for 2 wk before and 2 wk after challenging orally with Salmonella enterica serotype Typhimurium (SalT). Before bacterial challenge, ADFI was similar in all groups. After SalT challenge, ADFI of CON pigs was less (P < 0.05) than all other groups. Before challenge, pigs on MOA, FSM, and CT diets had greater (P < 0.05) ADG and G:F than CON pigs. After challenge (wk 3 to 4) and during the overall experimental period (wk 1 to 4), ADG of all treatment groups and G:F of all treatment groups except the LP group were greater (P < 0.05) than those of CON pigs. Relative to all other treatments, CON and LP pigs had greater (P < 0.05) bacterial shedding scores on d 7 after SalT challenge. At d 14 postchallenge, shedding scores declined (P < 0.05) in all treatment groups compared with CON pigs. Serum haptoglobin for all treatment groups increased from d 0 concentrations on d 6 postchallenge and declined to prechallenge concentrations on d 13 (P < 0.05). Circulating IGF-I concentrations declined from 2 to 6 d postchallenge and increased again by d 13 in ASB and LP groups, did not decline in FSM and CT groups, and continuously declined through d 13 in CON and LP groups (P < 0.05). However, in MOA group, IGF-I concentrations declined from preinfection concentrations on d 2, increased on d 4, and declined again until d 13 (P < 0.05). The serum concentrations of the cytokines IL-6 and IL-1β were not generally affected by SalT challenge. In conclusion, acute infection of growing pigs with SalT was associated with short-term febrile responses in most pigs and reductions in ADFI and ADG of CON pigs. Compared with the CON diet, ASB, FSM, and MOA diets had a similar benefit to the antibiotic-supplemented diet in improving the performance of growing pigs, especially after bacterial challenge. However, further work needs to be done to better understand their mode of action in this class of pigs.

Shewanella fodinae sp. nov., isolated from a coal mine and from a marine lagoon

Strains JC15(T) and JC19 were isolated from samples collected from different locations in India, including a coal mine and a marine lagoon. Both strains were Gram-stain-negative rods, motile by means of a single polar flagellum, catalase- and oxidase-positive, and hydrolysed casein, produced H(2)S and showed beta-haemolysis. Strain JC15(T) grew optimally at pH 6 (range pH 5-8) while strain JC19 grew optimally at pH 7 (range pH 6-9) and both had a growth temperature optimum of 30-37 degrees C (range 22-40 degrees C). Both strains could grow chemo-organoheterotrophically and chemolithoautotrophically. Neither strain required NaCl for growth and both could tolerate up to 9 % (w/v) NaCl, with optimum growth at 5 % NaCl. Vitamin B(12) was required as a growth factor by both strains. The major fatty acids were iso-C(15 : 0), C(17 : 1)omega8c and iso-C(13 : 0) 3-OH. The DNA G+C contents of strains JC15(T) and JC19 were 53.6 and 54.3 mol%, respectively. A phylogenetic tree based on 16S rRNA gene sequence analysis showed that strains JC15(T) and JC19 were most closely related to Shewanella haliotis DW01(T) (approximately 94 % sequence similarity) and to other members of the genus Shewanella. Genomic relatedness (DNA-DNA hybridization) between strains JC15(T) and JC19 is 88 %. On the basis of phenotypic and molecular genetic evidence, strain JC15(T) represents a novel species of the genus Shewanella, for which the name Shewanella fodinae sp. nov. is proposed. The type strain is JC15(T) (=CCUG 57102(T) =NBRC 105216(T) =KCTC 22506(T)).

Shewanella chilikensis sp. nov., a moderately alkaliphilic gammaproteobacterium isolated from a lagoon

A Gram-negative, motile, rod-shaped, facultatively anaerobic bacterium was isolated from sediment of Chilika Lagoon, a brackish water lagoon in India. The strain, designated JC5(T), was able to grow in the presence of 0-8.0 % NaCl and at pH 7.0-10.0. The isolate was positive for oxidase and catalase and exhibited alpha-haemolysis. The major fatty acids were iso-C(15 : 0) (18.3 %), C(16 : 0) (11.3 %), C(17 : 1)omega8c (13.1 %) and a summed feature, C(16 : 1)omega7c and/or C(16 : 1)omega6c (15.1 %). The genomic DNA G+C content was 54.6 mol%. A phylogenetic tree based on the 16S rRNA gene sequences showed that strain JC5(T) forms a lineage within the genus Shewanella and is closely related to Shewanella haliotis DW01(T) (98.0 %), Shewanella algae ATCC 51192(T) (97.6 %) and Shewanella marina C4(T) (95.8 %). Further, genomic DNA-DNA hybridization of strain JC5(T) with S. haliotis DW01(T) and S. algae ATCC 51192(T) showed relatedness of only 42 and 23 %, respectively. On the basis of phenotypic and molecular genetic evidence, strain JC5(T) represents a novel species of the genus Shewanella, for which the name Shewanella chilikensis sp. nov. is proposed. The type strain is JC5(T) (=CCUG 57101(T) =NBRC 105217(T) =KCTC 22540(T)).