Effect of inactivated Streptococcus pneumoniae as non-pathogenic particles on the severity of pneumonia caused by respiratory syncytial virus infection in mice

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We made inactivated Streptococcus pneumoniae (ISP) as non-pathogenic particles.

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We evaluated effects of ISP on development of pneumonia by RSV infection in mice.

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ISP didn’t show histopathological effects on lungs of RSV-infected mice.

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ISP reduced virus titer and infiltration of lymphocyte in the lungs.

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The inherent activity of ISP as particles in RSV infection is discussed.

The severity of pneumonia in respiratory syncytial virus (RSV) infection is strongly related to host immune response and external factors such as bacteria and environmental chemicals. We investigated the effect of inactivated Streptococcus pneumoniae (ISP) as non-pathogenic particles on the severity of pneumonia in RSV-infected mice. Mice were intranasally exposed to ISP before RSV infection. On day 5 post-infection, we examined tissues, virus titer, and infiltrated cells in the lungs. The ISP did not cause significant histopathological effects in the lungs of RSV infected mice, but reduced virus titer. It also reduced the ratio of lymphocyte infiltration into the lungs and consequently the ratio of macrophage increased. In addition, we found that ISP increased RANTES level in bronchoalveolar lavage fluid from RSV-infected mice on day 1 post-infection, but reduced type I interferon levels. Thus, ISP did not exacerbate pneumonia in RSV infection, rather, it might mildly reduce the severity. We characterize and discuss the inherent activity of ISP as non-pathogenic particles inducing the role of RANTES on the pneumonia in RSV infection.

Safety of tooth extraction in patients receiving direct oral anticoagulant treatment versus warfarin: a prospective observation study

The aim of this study was to compare the safety of tooth extraction in patients receiving direct oral anticoagulants (DOACs) or warfarin without cessation of their antithrombotic treatment. This prospective observational study included 367 patients undergoing tooth extraction (119 receiving DOACs and 248 receiving warfarin). All extractions in DOAC patients were performed 6-7h after taking DOACs in consideration of the half-life in blood under continued antithrombotic treatment. To examine the potential postoperative bleeding risk related to the time of extraction and the drug concentration of blood, activated partial thromboplastin time (APTT) in dabigatran and prothrombin time (PT) in rivaroxaban were measured three times after administration. A total of 390 tooth extractions were performed: 128 in the DOAC patients and 262 in warfarin patients. Postoperative bleeding occurred in four extractions (3.1%) in the DOAC group and in 23 (8.8%) in the warfarin group. There was no statistically significant difference between the two groups (odds ratio: 2.362, 95% confidence interval (CI) 0.819-6.815, p=0.112). APTT and PT prolongation in almost all cases decreased with time after taking the medicine. Our findings suggest that interruption of DOAC therapy is not necessary for tooth extraction if the procedure is performed at least 6h after the last dose.

Inhibitory effects of Sanguisorba officinalis root extract on HYBID (KIAA1199)-mediated hyaluronan degradation and skin wrinkling

OBJECTIVES

Hyaluronan (HA), an important constituent of extracellular matrix in the skin, has many biological activities such as hydration that contributes to firmness and bounciness of the skin. We have reported that reduction in HA in the papillary dermis and over-expression of HYBID (HYaluronan Binding protein Involved in hyaluronan Depolymerization, alias KIAA1199 or CEMIP), a key molecule for HA degradation in skin fibroblasts, are implicated in facial skin wrinkling in Japanese and Caucasian women. However, little or no information is available for substances which inhibit the HYBID-mediated HA degradation.

METHODS

Inhibition of Sanguisorba officinalis root extract and ziyuglycoside I, one of the components of Sanguisorba officinalis root extract, to the HYBID-mediated HA degradation was assessed by size-exclusion chromatography of HA depolymerized by stable transfectants of HYBID in HEK293 cells (HYBID/HEK293 cells) or normal human skin fibroblasts (Detroit 551 cells and NHDF-Ad cells). The HYBID mRNA and protein expression was examined by quantitative real-time PCR and immunoblotting in the skin fibroblasts treated with Sanguisorba officinalis root extract, and size distribution of newly produced HA was evaluated by preparing metabolically radiolabelled HA. A double-blind, randomized and placebo-controlled study was carried out in the 21 healthy Japanese women, who were topically treated with the formulation containing Sanguisorba officinalis root extract or the placebo on each side of the face including crow's foot area.

RESULTS

Sanguisorba officinalis root extract, but not ziyuglycoside I, abolished HYBID-mediated HA degradation by HYBID/HEK293 cells. Sanguisorba officinalis root extract also inhibited HYBID-mediated HA degradation in skin fibroblasts by down-regulating HYBID mRNA and protein expression. Although control untreated skin fibroblasts produced polydispersed HA, the cells treated with Sanguisorba officinalis root extract produced only high-molecular-weight HA. Treatment with Sanguisorba officinalis root extract-formulated lotion significantly improved skin elasticity, and reduced skin wrinkling scores at the outer eye corner compared with the placebo formulation.

CONCLUSION

Sanguisorba officinalis root extract showed an anti-HYBID-mediated HA degradation activity and anti-wrinkle activity on human facial skin, which is accompanied by the improvement in elasticity. Our study provides the possibility of a new strategy to inhibit HYBID-mediated HA degradation for anti-wrinkle care.

Fe-oxide concretions formed by interacting carbonate and acidic waters on Earth and Mars

Spherical Fe-oxide concretions on Earth, especially in Utah, USA, have been investigated as an analog of hematite spherules found in Meridiani Planum on Mars to support interpretations of water-rock interactions in early Mars. Although several formation mechanisms have been proposed for the Fe-oxide concretions on Earth, it is still unclear whether these mechanisms are viable because a precise formation process and precursor of the concretions are missing. This paper presents evidence that Fe-oxide concretions in Utah and newly found Fe-oxide concretions in Mongolia had spherical calcite concretions as precursors. Different formation stages of calcite and Fe-oxide concretions observed, both in Utah and Mongolia, indicate that calcite concretions initially formed within eolian sandstone strata and were dissolved by infiltrating Fe-rich acidic waters to form spherical FeO(OH) crusts due to pH buffering. The similarity between these Fe-oxide concretions on Earth and the hematite spherule occurrences in Meridiani Planum, combined with evidence of acid sulfate water influences on Mars, suggest that the hematite spherules also formed from dissolution of preexisting carbonate spherules possibly formed under a dense carbon dioxide early martian atmosphere.

Antiviral activity of hypothiocyanite produced by lactoperoxidase against influenza A and B viruses and mode of its antiviral action

Hypothiocyanite (OSCN-) is a natural component of human saliva and is produced by the lactoperoxidase (LPO)/thiocyanate/hydrogen peroxide (H2O2) system. OSCN- has been previously shown to exhibit antiviral activity against influenza viruses (IFV) A/H1N1/2009 and A/H1N2/2009 in vitro as well as antimicrobial and antifungal activities. We elucidated the antiviral activity of OSCN- against both IFV types A and B and the mode of its antiviral action. OSCN- was produced constantly at 900 ± 200 μmol/l in Na3PO4 buffer solution containing NaSCN and LPO in the presence of H2O2 as an original OSCN- solution. In a plaque reduction assay, IFV A/PR/8/34 (H1N1), A/Fukushima/13/43 (H3N2), B/Singapore/222/97, and B/Fukushima/15/93 were exposed to various concentrations of OSCN- for 0 to 30 min before adsorption to MDCK cells, and plaque formation was examined. OSCN- exhibited significant similar antiviral activities against all four viruses without cytotoxicity, and the EC50 values for them were from 57 ± 16 to 148 ± 27 μmol/l regardless of the exposure times. The exposure of MDCK cells to OSCN- before viral adsorption did not affect its anti-IFV activity (EC50: more than 450 μmol/l), but the exposure after viral adsorption affected it moderately (EC50: 380 ± 40 μmol/l). Moreover, the exposure of virus particles to OSCN- at 450 μmol/l did not affect the hemagglutinin activity of IFV in hemagglutination inhibition assay. These results suggest that the attachment of OSCN- to the viral envelope critically contributes to the mode of antiviral action of OSCN- without interfering with viral adsorption. Keywords: hypothiocyanite; influenza virus type A; influenza virus type B; lactoperoxidase; antiviral activity.

Broad-spectrum antibiotic prescriptions are discontinued unevenly throughout the week

In order to investigate prescribing patterns of in-hospital broad-spectrum antibiotics (antimeticillin-resistant Staphylococcus aureus drugs, carbapenems and piperacillin/tazobactam), data on the distribution of antibiotic initiation and discontinuation throughout the week were analysed at Osaka University Hospital, Japan. No significant differences in the number of initiations were found between weekdays. However, broad-spectrum antibiotics were disproportionately discontinued on Tuesdays or on the second day after a holiday. This study suggests that broad-spectrum antibiotics tend to be continued over weekends or holidays and discontinued thereafter; this is likely to be due to behavioural factors beyond medical indications, and needs to be addressed in future antimicrobial stewardship initiatives.

Transition of Spleen Volume Long After Pediatric Living Donor Liver Transplantation for Biliary Atresia

PURPOSE

After undergoing the Kasai procedure for biliary atresia (BA), most patients develop severe splenomegaly that tends to be improved by liver transplantation. However, fluctuations in splenic volume long after transplantation remain to be elucidated.

PATIENTS AND METHODS

Seventy-one consecutive patients who had undergone pediatric living donor liver transplantation (LDLT) for BA were followed up in our outpatient clinic for 5 years. They were classified into 3 groups according to their clinical outcomes: a good course group (GC, n = 41) who were maintained on only 1 or without an immunosuppressant, a liver dysfunction group (LD, n = 18) who were maintained on 2 or 3 types of immunosuppressants, and a vascular complication group (VC, n = 11). Splenic and hepatic volumes were calculated by computed tomography in 464 examinations and the values compared before and after the treatment, especially in the VC group.

RESULTS

Splenic volume decreased exponentially in the GC group, with splenic volume to standard spleen volume ratio (SD) being 1.59 (0.33) 5 years after liver transplantation. Splenic volume to standard spleen volume ratios were greater in the VC and LD groups than in the GC group. Patients in the VC group with portal vein stenosis developed liver atrophy and splenomegaly, whereas those with hepatic vein stenosis developed hepatomegaly and splenomegaly. Interventional radiation therapy tended to improve the associated symptoms.

CONCLUSIONS

Fluctuations in splenic volume long after pediatric LDLT for BA may reflect various clinical conditions. Evaluation of both splenic and hepatic volumes can facilitate understanding clinical conditions following pediatric LDLT.

Albumin, Hemoglobin, and the Trajectory of Cognitive Function in Community-Dwelling Older Japanese: A 13-Year Longitudinal Study

BACKGROUND

Cognitive function can substantially decline over a long period, and understanding the trajectory of cognitive function is important. However, little is known about the linkage between nutritional biomarkers and long-term cognitive change.

OBJECTIVES

We analyzed 13-year longitudinal data for older Japanese to examine the associations of serum albumin and hemoglobin levels with the trajectory of cognitive function.

DESIGN

Longitudinal study.

SETTING

Community-based.

PARTICIPANTS

A total of 1,744 community-dwelling adults aged 65 years or older who participated in annual health examinations in Kusatsu town, Gunma Prefecture, Japan, from 2002-2014.

MEASUREMENTS

Cognitive function was assessed annually by the Mini-Mental State Examination (MMSE). Albumin and hemoglobin levels at baseline (the year when a respondent first participated in the health examination) were divided into quartiles. Hierarchical linear modeling was used to analyze intrapersonal and interpersonal differences in cognitive function.

RESULTS

Participants' MMSE scores decreased at an accelerated rate over the 13-year period. Participants with the lowest baseline albumin level (below the first quartile line) showed a greater accelerated decline in MMSE scores over time, compared with those with the highest level (above the third quartile line). Moreover, MMSE scores in participants with a lower hemoglobin level and lower MMSE score at baseline tended to decline faster over time at an accelerated rate.

CONCLUSIONS

These findings yield new insights about the complex and diverse roles of these nutritional biomarkers on the trajectory of cognitive function in old age.

A Flow Cytometry Method for Dissecting the Cell Differentiation Process of Entamoeba Encystation

Amoebiasis is caused by Entamoeba histolytica infection, a protozoan parasite belonging to the phylum Amoebozoa. This parasite undergoes a fundamental cell differentiation process from proliferative trophozoite to dormant cyst, termed “encystation.” The cysts formed by encystation are solely responsible for the transmission of amoebiasis; therefore, Entamoeba encystation is an important subject from both biological and medical perspectives. Here, we have established a flow cytometry strategy for not only determining the percentage of formed cysts but also for monitoring changes in cell populations during encystation. This strategy together with fluorescence microscopy enables visualization of the cell differentiation process of Entamoeba encystation. We also standardized another flow cytometry protocol for counting live trophozoites. These two different flow cytometry techniques could be integrated into 96-well plate-based bioassays for monitoring the processes of cyst formation and trophozoite proliferation, which are crucial to maintain the Entamoeba life cycle. The combined two systems enabled us to screen a chemical library, the Pathogen Box of the Medicine for Malaria Venture, to obtain compounds that inhibit either the formation of cysts or the proliferation of trophozoites, or both. This is a prerequisite for the development of new drugs against amoebiasis, a global public health problem. Collectively, the two different 96-well plate-based Entamoeba bioassay and flow cytometry analysis systems (cyst formation and trophozoite proliferation) provide a methodology that can not only overcome the limitations of standard microscopic counting but also is effective in applied as well as basic Entamoeba biology.

Interleukin-27 controls basal pain threshold in physiological and pathological conditions

Numerous studies have shown that pain sensation is affected by various immune molecules, such as cytokines, in tissues comprising the sensory pathway. Specifically, it has been shown that interleukin (IL)-17 promotes pain behaviour, but IL-10 suppresses it. IL-27 has been reported to have an anti-inflammatory effect through regulation of T cell differentiation, resulting in reduced IL-17 and induction of IL-10. Thus, we hypothesised that IL-27 would have some regulatory role in pain sensation. Here, we provide evidence that endogenous IL-27 constitutively controls thresholds for thermal and mechanical sensation in physiological and pathological conditions. Mice lacking IL-27 or its receptor WSX-1 spontaneously showed chronic pain-like hypersensitivity. Reconstitution of IL-27 in IL-27-deficient mice reversed thermal and mechanical hypersensitive behaviours. Thus, unlike many other cytokines induced by inflammatory events, IL-27 appears to be constitutively produced and to control pain sensation. Furthermore, mice lacking IL-27/WSX-1 signalling showed additional hypersensitivity when subjected to inflammatory or neuropathic pain models. Our results suggest that the mechanisms underlying hypersensitive behaviours caused by the ablation of IL-27/WSX-1 signalling are different from those underlying established chronic pain models. This novel pain control mechanism mediated by IL-27 might indicate a new mechanism for the chronic pain hypersensitivity.

Reduction of hyaluronan and increased expression of HYBID (alias CEMIP and KIAA1199) correlate with clinical symptoms in photoaged skin

BACKGROUND

Hyaluronan (HA) metabolism in skin fibroblasts is mediated by HYBID (hyaluronan binding protein involved in hyaluronan depolymerization, alias CEMIP and KIAA1199) and the HA synthases HAS1 and HAS2. However, photoageing-dependent changes in HA and their molecular mechanisms, and the relationship between HA metabolism and clinical symptoms in photoaged skin remain elusive.

OBJECTIVES

We examined the amount, size and tissue distribution of HA and expression levels of HYBID, HAS1 and HAS2 in photoaged skin, and analysed their relationship with the degree of photoageing.

METHODS

Photoageing-dependent changes of HA were investigated by studying skin biopsies isolated from photoprotected and photoexposed areas of the same donors, and the relationships between HA and photoageing symptoms such as skin wrinkling and sagging were examined.

RESULTS

Skin biopsy specimens showed that the amount and size of HA are decreased in photoexposed skin compared with photoprotected skin, and this was accompanied by increased expression of HYBID and decreased expression of HAS1 and HAS2. Histologically, HA staining in the papillary dermis was decreased in photoexposed skin, showing reverse correlation with HYBID expression. HYBID expression in the photoexposed skin directly correlated with skin roughness and sagging parameters, and the reduced HA staining in the papillary dermis in the photoexposed skin positively correlated with these symptoms.

CONCLUSIONS

These data demonstrate that imbalance between HYBID-mediated HA degradation and HAS-mediated HA synthesis may contribute to enhanced HA catabolism in photoaged skin, and suggest that HYBID-mediated HA reduction in the papillary dermis is related to skin wrinkling and sagging of photoaged skin.

Murine γ-Herpesvirus 68 Induces Severe Lung Inflammation in IL-27-Deficient Mice with Liver Dysfunction Preventable by Oral Neomycin

IL-27 is an immunoregulatory cytokine consisting of p28 and EBI3. Its receptor also has two subunits, WSX1 and gp130. Although IL-27 promotes Th1 differentiation in naive T cells, it also induces IL-10 expression in effector Th1 cells to curtail excessive immune responses. By using p28-deficient mice and WSX1-deficient mice (collectively called IL-27-deficient mice), we examined the role of IL-27 in primary infection by murine γ-herpesvirus 68 (MHV68), a murine model of EBV. Upon airway infection with MHV68, IL-27-deficient mice had more aggravated lung inflammation than wild-type mice, although MHV68 infection per se was better controlled in IL-27-deficient mice. Although epithelial cells and alveolar macrophages were primarily infected by MHV68, interstitial macrophages and dendritic cells were the major producers of IL-27. The lung inflammation of IL-27-deficient mice was characterized by more IFN-γ-producing CD8⁺ T cells and fewer IL-10-producing CD8⁺ T cells than that of wild-type mice. An infectious mononucleosis-like disease was also aggravated in IL-27-deficient mice, with prominent splenomegaly and severe hepatitis. Infiltration of IFN-γ-producing effector cells and upregulation of the CXCR3 ligand chemokines CXCL9, CXCL10, and CXCL11 were noted in the liver of MHV68-infected mice. Oral neomycin effectively ameliorated hepatitis, with decreased production of these chemokines in the liver, suggesting that the intestinal microbiota plays a role in liver inflammation through upregulation of these chemokines. Collectively, IL-27 is essential for the generation of IL-10-producing effector cells in primary infection by MHV68. Our findings may also provide new insight into the mechanism of hepatitis associated with infectious mononucleosis.

Apaf1 plays a negative regulatory role in T cell responses by suppressing activation of antigen-stimulated T cells

Apaf1 is a critical component of the apoptosome and initiates apoptosis downstream mitochondrial damages. Although the importance of Apaf1 in embryonic development was shown, the role of Apaf1 in immune responses, especially T cell responses, has yet to be elucidated. We generated T cell-specific Apaf1-deficient mice (Lck-Cre-Apaf1^f/f mice) and examined the antigen-specific delayed-type hypersensitivity (DTH). Lck-Cre-Apaf1^f/f mice exhibited exacerbation of DTH responses as compared with Apaf1-sufficient control mice. In Lck-Cre-Apaf1^f/f mice, antigen-specific T cells proliferated more, and produced more inflammatory cytokines than control T cells. Apaf1-deficient T cells from antigen-immunized mice showed higher percentages of activation phenotypes upon restimulation in vitro. Apaf1-deficient T cells from naive (non-immunized) mice also showed higher proliferation activity and cytokine production over control cells. The impact of Apaf1-deficiency in T cells, however, was not restored by a pan-caspase inhibitor, suggesting that the role of Apaf1 in T cell responses was caspase-independent/non-apoptotic. These data collectively demonstrated that Apaf1 is a negative regulator of T cell responses and implicated Apaf1 as a potential target for immunosuppressive drug discovery.

Relationship of hyaluronan and HYBID (KIAA1199) expression with roughness parameters of photoaged skin in Caucasian women

BACKGROUND

Hyaluronan (HA) is an important constituent of extracellular matrix (ECM) in the skin, and HA degradation mediated by HYBID (KIAA1199) is suggested to be implicated in facial skin wrinkling in Japanese women. Ethnic difference in skin wrinkle formation is known between Caucasian and Japanese women, but no information is available for the relations of HA and HYBID expression levels with skin wrinkling in Caucasian women.

METHODS

The skin surface roughness at the eye corner of the Caucasian female subjects was measured, and the skin specimens biopsied from the same areas were subjected to microarray gene analysis, HA staining, and immunohistochemistry for HYBID.

RESULTS

Among the ECM genes and those related to ECM metabolism, only HYBID expression levels positively correlated with the skin roughness parameters. When the skin sample groups with high expression of HYBID or low expression of HYBID were compared, the HA staining intensity and the ratio of HYBID-immunoreactive cells to total cells in the superficial dermis were significantly reduced and increased in the high-HYBID-expression group compared with the low-HYBID-expression group, respectively.

CONCLUSION

Our data suggest that like Japanese women, HYBID-mediated reduction of HA in the superficial dermis is involved in the formation of wrinkles in Caucasian women.

Perinatal exposure to tetrabromobisphenol A (TBBPA), a brominated flame retardant, exacerbated the pneumonia in respiratory syncytial virus (RSV)-infected offspring mice

To investigate the effects of perinatal exposure to tetrabromobisphenol A (TBBPA), a brominated flame retardant, on the immune system, a respiratory syncytial virus (RSV) infection mouse model was utilized. Female mice were exposed to TBBPA mixed with the diet from 10 days after conception to weaning on postnatal day 21. Offspring mice were infected intranasally with A2 strain of RSV. Although no general toxicological sign was observed, the pulmonary viral titers of offspring mice exposed to 0.1% TBBPA were significantly increased compared with the control on day 5 post-infection. TBBPA did not affect RSV growth in vitro. Histopathological analysis confirmed that the exacerbation of interstitial pneumonia was due to TBBPA- exposure in the lung tissues in RSV-infected offspring. Moreover, gene expression of interleukin (IL)-24 was shown to be elevated typically in the lung tissues of TBBPA-treated offspring by a DNA microarray and was also confirmed by immunohistopathological analysis using an anti-IL-24 antibody. Thus, developmental exposure to TBBPA affected the immune response to RSV infection, resulting in the exacerbation of pneumonia. Thus, IL-24 should be a key molecule to understand the mechanism of action of TBBPA.