Measurement of the Positive Muon Anomalous Magnetic Moment to 0.20 ppm

We present a new measurement of the positive muon magnetic anomaly, a_{μ}≡(g_{μ}-2)/2, from the Fermilab Muon g-2 Experiment using data collected in 2019 and 2020. We have analyzed more than 4 times the number of positrons from muon decay than in our previous result from 2018 data. The systematic error is reduced by more than a factor of 2 due to better running conditions, a more stable beam, and improved knowledge of the magnetic field weighted by the muon distribution, ω[over ˜]_{p}^{'}, and of the anomalous precession frequency corrected for beam dynamics effects, ω_{a}. From the ratio ω_{a}/ω[over ˜]_{p}^{'}, together with precisely determined external parameters, we determine a_{μ}=116 592 057(25)×10^{-11} (0.21 ppm). Combining this result with our previous result from the 2018 data, we obtain a_{μ}(FNAL)=116 592 055(24)×10^{-11} (0.20 ppm). The new experimental world average is a_{μ}(exp)=116 592 059(22)×10^{-11} (0.19 ppm), which represents a factor of 2 improvement in precision.

Measurement of the Positive Muon Anomalous Magnetic Moment to 0.46 ppm

We present the first results of the Fermilab National Accelerator Laboratory (FNAL) Muon g-2 Experiment for the positive muon magnetic anomaly a_{μ}≡(g_{μ}-2)/2. The anomaly is determined from the precision measurements of two angular frequencies. Intensity variation of high-energy positrons from muon decays directly encodes the difference frequency ω_{a} between the spin-precession and cyclotron frequencies for polarized muons in a magnetic storage ring. The storage ring magnetic field is measured using nuclear magnetic resonance probes calibrated in terms of the equivalent proton spin precession frequency ω[over ˜]_{p}^{'} in a spherical water sample at 34.7 °C. The ratio ω_{a}/ω[over ˜]_{p}^{'}, together with known fundamental constants, determines a_{μ}(FNAL)=116 592 040(54)×10^{-11} (0.46 ppm). The result is 3.3 standard deviations greater than the standard model prediction and is in excellent agreement with the previous Brookhaven National Laboratory (BNL) E821 measurement. After combination with previous measurements of both μ^{+} and μ^{-}, the new experimental average of a_{μ}(Exp)=116 592 061(41)×10^{-11} (0.35 ppm) increases the tension between experiment and theory to 4.2 standard deviations.

Depressive symptoms, professional quality of life and turnover intention in Korean nurses

AIM

The purpose of this study was to identify the effects of depressive symptoms and professional quality of life on turnover intention.

BACKGROUND

The high turnover rate of nurses is a critical healthcare issue globally.

INTRODUCTION

Nurses often experience depressive symptoms and compassion fatigue due to the efforts of patient care. The impact of such psychological health issues on turnover intention needs to be confirmed.

METHODS

Participants were 10 163 female nurses who completed an online or mobile survey using the Korea Nurses' Health Study. To identify the influencing factors on the turnover intention of nurses, descriptive statistics, spearman's correlation coefficients and multivariable ordinal logistic regression were performed.

RESULTS

The turnover intention increased by about 2.81-4.60 times when depressive symptom was moderate or more, 1.14 times when secondary traumatic stress disorder was moderate or more, and 1.54 times when burnout was moderate or more. When compassion satisfaction was moderate or high, the turnover intention decreased by 0.72 and 0.52 times.

DISCUSSION

Korean nurses demonstrated high levels of depressive symptoms, secondary traumatic stress and burnout, while demonstrating lower levels of compassion satisfaction. The results of this study demonstrate that depressive symptoms, secondary traumatic stress, burnout and compassion satisfaction affect turnover intention.

CONCLUSIONS

To reduce nurses' turnover intention, it is necessary to reduce depressive symptoms and enhance the quality of professional life.

IMPLICATIONS FOR NURSING AND HEALTH POLICY

Hospital managers need to maintain adequate nurse-to-patient ratios and provide nurses with a supportive work environment. Also, health policymakers need to identify factors affecting hospital nurses' turnover intention and provide strategies to address them. These conditions may reduce the excessive workload placed on nurses, thereby preventing depression and burnout and improving nurses' quality of work-life.

Binge eating disorder and depressive symptoms among females of child-bearing age: the Korea Nurses' Health Study

BACKGROUND

Most studies regarding the relationship between binge eating disorder (BED) and depression have targeted obese populations. However, nurses, particularly female nurses, are one of the vocations that face these issues due to various reasons including high stress and shift work. This study investigated the prevalence of BED and the correlation between BED and severity of self-reported depressive symptoms among female nurses in South Korea.

METHODS

Participants were 7,267 female nurses, of which 502 had symptoms of BED. Using the propensity score matching (PSM) technique, 502 nurses with BED and 502 without BED were included in the analyses. Data were analyzed using descriptive statistics, Spearman's correlation, and multivariable ordinal logistic regression analysis.

RESULTS

The proportion of binge eating disorder was 6.90% among the nurses, and 81.3% of nurses displayed some levels of depressive symptoms. Multivariable ordinal logistic regression analysis revealed that age (40 years old and older), alcohol consumption (frequent drinkers), self-rated health, sleep problems, and stress were associated with self-reported depression symptoms. Overall, after adjusting for confounders, nurses with BED had 1.80 times the risk (95% CI = [1.41-2.30]; p-value < 0.001) of experiencing a greater severity of self-reported depression symptoms.

CONCLUSIONS

Korean female nurse showed a higher prevalence of both binge eating disorder and depressive symptoms, and the association between the two factors was proven in the study. Therefore, hospital management and health policy makers should be alarmed and agreed on both examining nurses on such problems and providing organized and systematic assistance.

Syntenin regulates TGF-β1-induced Smad activation and the epithelial-to-mesenchymal transition by inhibiting caveolin-mediated TGF-β type I receptor internalization

Syntenin, a tandem PDZ domain containing scaffold protein, functions as a positive regulator of cancer cell progression in several human cancers. We report here that syntenin positively regulates transforming growth factor (TGF)-β1-mediated Smad activation and the epithelial-to-mesenchymal transition (EMT) by preventing caveolin-1-mediated internalization of TGF-β type I receptor (TβRI). Knockdown of syntenin suppressed TGF-β1-mediated cell migration, transcriptional responses and Smad2/3 activation in various types of cells; however, overexpression of syntenin facilitated TGF-β1-mediated responses. In particular, syntenin knockdown abolished both the basal and TGF-β1-mediated repression of E-cadherin expression, as well as induction of vimentin expression along with Snail and Slug upregulation; thus, blocking the TGF-β1-induced EMT in A549 cells. In contrast, overexpression of syntenin exhibited the opposite effect. Knockdown of syntenin-induced ubiquitination and degradation of TβRI, but not TGF-β type II receptor, leading to decreased TβRI expression at the plasma membrane. Syntenin associated with TβRI at its C-terminal domain and a syntenin mutant lacking C-terminal domain failed to increase TGF-β1-induced responses. Biochemical analyzes revealed that syntenin inhibited the interaction between caveolin-1 and TβRI and knockdown of syntenin induced a massive internalization of TβRI and caveolin-1 from lipid rafts, indicating that syntenin may increase TGF-β signaling by inhibiting caveolin-1-dependent internalization of TβRI. Moreover, a positive correlation between syntenin expression and phospho-Smad2 levels is observed in human lung tumors. Taken together, these findings demonstrate that syntenin may act as an important positive regulator of TGF-β signaling by regulating caveolin-1-mediated internalization of TβRI; thus, providing a novel function for syntenin that is linked to cancer progression.

Altered GABA and somatostatin modulation of proprioceptive feedback after spinal cord injury in lamprey

While various changes occur after spinal cord lesions, their influence on functional recovery is generally unclear. We have shown changes in proprioceptor and locomotor network properties below lesion sites in the lamprey spinal cord. The proprioceptive system offers a particularly tractable model for analyzing these changes. Here, we have sought evidence for changes in neuromodulatory effects below lesion sites by comparing the effects of gamma-aminobutyric acid (GABA) and somatostatin, both of which are located around the edge cells, on proprioceptive responses in lesioned and unlesioned spinal cords. Exogenously applied GABA significantly reduced or abolished bending-evoked responses in unlesioned animals. In lesioned animals bending-evoked responses were stronger and certain of the effects of exogenously applied GABA were reduced. However, blocking endogenous GABA with bicuculline significantly potentiated responses in lesioned but not unlesioned animals. This suggested that the potentiated responses in lesioned animals were nevertheless associated with stronger tonic GABAergic inhibition. There were significant differences in these effects when lesioned animals were separated on the basis of their degree of recovery: notably, bicuculline only potentiated responses in animals that recovered good locomotor function, suggesting a need for raised endogenous GABA levels. Somatostatin alone did not affect edge cell responses in lesioned or unlesioned animals, but in lesioned animals it reduced and thus further weakened the inhibitory effects of GABA. There are thus multiple changes in sensory modulation in the lesioned spinal cord, and differences in these effects may influence the degree of recovery.

Triketoacid inhibitors of HIV-integrase: A new chemotype useful for probing the integrase pharmacophore

Integrase is one of three enzymes expressed by HIV and represents a validated target for therapy. This study reports on the discovery of a new triketoacid-based chemotype that selectively inhibits the strand transfer reaction of HIV-integrase. SAR studies showed that the template binds to integrase in a manner similar to the diketoacid-based inhibitors. Moreover, comparison of the new chemotype to two different diketoacid templates led us to propose two aryl-binding domains in the inhibitor binding site. This information was used to design a new diketoacid template with improved activity against the enzyme.

Expression of inflammatory cytokines in pigs experimentally infected with Mycoplasma hyopneumoniae

The expression of interleukin-1 (IL-1), tumour necrosis factor-alpha (TNF-alpha) and IL-6 were studied over a period of 35 days in the lungs of pigs experimentally infected with Mycoplasma hyopneumoniae, by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR), morphometric analysis and in-situ hybridization. Fifteen colostrum-deprived pigs aged 14 days were inoculated intranasally with M. hyopneumoniae. IL-1, TNF-alpha and IL-6 were detected by RT-PCR in the lungs of the infected pigs from 7 days post-inoculation (dpi) onwards, but not in the uninfected control pigs. Concurrent expression of all three cytokines was always observed, in association with lung lesions. Inflammatory cytokine-positive cells were detected in the lungs at 7 dpi, their number increasing at 21dpi, and decreasing thereafter. The results suggest that such cytokines play a role in mediating and regulating inflammation in M. hyopneumoniae infection.

The replication of canine herpesvirus (CHV) induces apoptosis in canine kidney cell line: short communication

The alphaherpesvirus canine herpesvirus (CHV) was tested in order to determine whether or not it has apoptotic potential. We have demonstrated that lytic replication of CHV resulted in induction of apoptosis. This phenomenon was confirmed using different techniques including in situ TUNEL assay and DNA laddering. The apoptotic activity of CHV might influence the pathobiology of this virus.

Enhancement of in situ hybridization to detect bovine herpesvirus 4 in paraffin sections

In situ hybridization (ISH) protocols including different pre-treatment regimes were developed and compared for their effects on detecting bovine herpesvirus 4 (BoHV-4) in formalin fixed, paraffin embedded tissue. Results were compared for the hybridization and background signal intensities, and cellular morphology. We found that optimum results were obtained using enzyme treatment-thermal cycling as a pre-treatment of ISH. The results showed that the combination of protease and thermal cycling would be recommended as a means of supplementing in situ hybridization methods, especially when using long-term formalin fixed, paraffin-embedded tissue.

Experimental infection of piglets with a korean strain of porcine epidemic diarrhoea virus

Thirty colostrum-deprived piglets aged 1 day were inoculated with a Korean strain of porcine epidemic diarrhoea virus (PEDV). The purpose was to elucidate the pathogenicity and viral distribution in PEDV-infected piglets over a period of 60 h, by morphometric analysis, in-situ hybridization and immunohistochemistry. At 24-60 h post-inoculation (hpi), the villous height/crypt depth (VH/CD) ratio of infected pigs was significantly less than that of control pigs. Positive cells typically exhibited a dark black reaction product (in-situ hybridization) or brown reaction product (immunohistochemistry) in the cytoplasm, without background staining. PEDV nucleic acid and antigen were detected in the duodenum, jejunum and ileum of experimentally infected pigs. The results suggested that the Korean strain was virulent and caused severe villous atrophy in the small intestine.

Lytic replication of Human herpesvirus 8 and induction of apoptosis

Although many viruses can induce apoptosis in infected cells, large DNA viruses, such as poxviruses, herpesviruses and adenoviruses, usually exhibit the ability to suppress the induction of apoptosis in the infected cells. We investigated the ability of Human herpesvirus 8 (HHV-8) to protect cells from apoptosis induced by the virus. HHV-8 has been shown to harbor genes with anti-apoptotic capacity. However, we demonstrate here that a lytic replication of HHV-8 resulted in induction of apoptosis using different techniques to detect apoptosis. Therefore, despite the presence of anti-apoptotic genes in its genome, HHV-8 could complete its cycle of productive infection while inducing apoptosis in infected cells. This finding might have implications for the pathobiology of HHV-8 and other gamma herpesviruses in vivo.

A sensitive and specific detection of Human herpesvirus 8 by polymerase chain reaction and dot blot hybridization

Polymerase chain reaction (PCR) is a powerful technique of detecting Human herpesvirus 8 (HHV-8), but has a limited sensitivity and specificity. A new assay of HHV-8 based on combination of PCR with dot blot hybridization (DBH) was developed and evaluated for its sensitivity and specificity. An HHV-8-specific primer pair, ORF26out was used for amplification of target DNA. When the PCR product was detected visually the limit of detection was 0.1 ng DNA isolated from HHV-8-infected BC-3 cells. For DBH, the DNA amplified with the primer pair ORF26in specific for HHV-8 was labeled with digoxigenin (DIG). This DIG-labeled probe was capable of detecting 1.0 ng of DNA isolated from HHV-8-infected BC-3 cells. On the other hand, PCR combined with DBH (PCR/DBH) was more sensitive than PCR or DBH alone and also very specific. The sensitivity of PCR/DBH was higher than that of PCR and DBH alone. The PCR/DBH assay can be applied efficiently to confirm the presence of HHV-8 in clinical samples and to differentiate specifically HHV-8 infection from other viral infections.

Functional expression of the Vibrio parahaemolyticus Na+/galactose (vSGLT) cotransporter in Xenopus laevis oocytes

We have successfully expressed a bacterial cotransporter in a functional form in the Xenopus laevis oocyte expression system. The goals were to compare the kinetics and selectivity of the cotransporter expressed in oocytes with those obtained in bacteria and in proteoliposomes, and to determine if it is possible to measure the electrical properties of the bacterial cotransporter expressed in oocytes. The Vibrio parahaemolyticus Na+/galactose cotransporter (vSGLT) expressed in oocytes has functional properties that are similar to those expressed in bacteria and those of the purified cotransporter reconstituted into liposomes. vSGLT is a Na+-dependent transporter that is saturable with Na+ (K(0.5)=17 mM) and D-galactose (K(0.5)=237 microM) and is sensitive to both D-fucose and phlorizin. In addition, vSGLT in oocytes shows a sugar specificity in the order of D-galactose >D-fucose > D-glucose, distinguishing it from the animal members of the Na+/glucose cotransporter family. The level of transport by vSGLT in oocytes is lower overall (V(max) approximately 10 pmol/oocyte/hour) compared to other plant and animal cotransporters (V(max) approximately 1000 pmol/oocyte/hour). The low level of expression does not permit us to carry out electrophysiological studies of the bacterial cotransporter. This study shows the potential and unique advantages of utilizing a eukaryotic oocyte expression system to study bacterial cotransporters.

Body weight, self-esteem, and depression in Korean female

The purpose of this study was to examine whether body mass index (BMI) and perception of a body weight problem predict level of self-esteem and depression in Korean female adolescents. The sample consisted of 303 females, ranging in age from 15 to 19 years, who were attending four high schools located in Seoul, Korea. BMI and desired BMI were calculated based on self-reported weight and height. Self-perception of having a weight problem was evaluated by one question: "Do you see yourself as having a weight problem?" Self-esteem was measured using the Rosenberg Self-Esteem Scale, and depression was measured using the Center for Epidemiologic Studies Depression Scale. Based on BMI, 18.2% of the females were underweight, 79.2% were of normal weight, and 2.6% were overweight. Based on desired BMI, 78.5% of the females desired to be underweight. Results showed that perception of a weight problem, but not BMI, contributed significantly to the prediction of level of self-esteem and depression. In addition, there was a significant positive correlation between BMI and perception of a weight problem.

Cutting edge: membrane lymphotoxin regulates CD8(+) T cell-mediated intestinal allograft rejection

Blocking the CD28/B7 and/or CD154/CD40 costimulatory pathways promotes long-term allograft survival in many transplant models where CD4(+) T cells are necessary for rejection. When CD8(+) T cells are sufficient to mediate rejection, these approaches fail, resulting in costimulation blockade-resistant rejection. To address this problem we examined the role of lymphotoxin-related molecules in CD8(+) T cell-mediated rejection of murine intestinal allografts. Targeting membrane lymphotoxin by means of a fusion protein, mAb, or genetic mutation inhibited rejection of intestinal allografts by CD8(+) T cells. This effect was associated with decreased monokine induced by IFN-gamma (Mig) and secondary lymphoid chemokine (SLC) gene expression within allografts and spleens respectively. Blocking membrane lymphotoxin did not inhibit rejection mediated by CD4(+) T cells. Combining disruption of membrane lymphotoxin and treatment with CTLA4-Ig inhibited rejection in wild-type mice. These data demonstrate that membrane lymphotoxin is an important regulatory molecule for CD8(+) T cells mediating rejection and suggest a strategy to avoid costimulation blockade-resistant rejection.

Regulation of Akt/PKB activation by tyrosine phosphorylation

Activation of Akt/PKB by growth factors requires multiple phosphorylation events. Phosphorylation of Thr(308) and Ser(473) of Akt by its upstream kinase(s) or autophosphorylation is critical for optimal activation of its kinase activity. Here, we present evidence that tyrosine phosphorylation is required for Akt activation. Epidermal growth factor treatment induces tyrosine phosphorylation of Akt in COS1 and PC3M cells, which is abrogated by PP2, a selective inhibitor for Src family tyrosine kinases. Elevated Akt activity is observed in v-Src transformed NIH3T3 cells, which is accompanied with increased tyrosine phosphorylation of Akt. Akt activity induced by growth factors is significantly reduced in SYF cells lacking Src, Yes, and Fyn, which can be restored by introducing c-Src, but not the kinase-inactive Src, back to these cells. Furthermore, we have identified two tyrosine residues near the activation loop of Akt that are important for its activation. Substitution of these residues with phenylalanine abolishes Akt kinase activity stimulated by growth factors. These two YF mutants fail to block Forkhead transcription factor activity in 293 cells and are unable to prevent apoptosis induced by matrix detachment. Our data suggest that, in addition to phosphorylation of Thr(308) and Ser(473), tyrosine phosphorylation of Akt may be essential for its biological function.

Immunohistochemical study of the expression of alpha-smooth muscle actin and the proliferation marker Ki-67 of glomerulonephritis

The aim of this study was to determine the relationship of alpha-smooth muscle actin (ASMA) and the proliferation marker Ki-67 of glomerulonephritis (GN). Immunohistochemical stainings with the usual streptavidin-biotin peroxidase method were performed on 86 renal biopsies using monoclonal 1A4 and Ki-67. The results of the quantitative evaluation of ASMA and Ki-67 were analyzed for the correlation between positive value of ASMA and Ki-67 in different GN. ASMA expressions of glomeruli were highest in acute post-infectious GN [APGN; 16.9 Fraction Volume (FV)%], followed by unclassified proliferative GN (UnGN; 12.5 FV%), membranoproliferative GN (MPGN; 8.5 FV%), lupus nephritis (LupusN; 6.3 FV%), IgA nephritis (IgAN; 5.6 FV%), and normal control (0.1 FV%). The Ki-67 staining was considerably elevated in lupusN (4.3 Ki-67 positives/glomerulus), APGN (2.7), MPGN (2.5), UnGN (1.66), IgAN (0.5), compared with that in normal control group (0.1 Ki-67 positives/glomerulus). Ki-67 value in each category of glomerular diseases was significantly different from that in the control biopsies (p<0.004). The relationship between morphometric results of ASMA and Ki-67 was statistically significant regardless of the diagnosis. (rs=0.425, p=0.000, ASMA= 0.1113+0.1665 Ki-67). In conclusion, the immunohistochemical assessment of ASMA and Ki-67 expression in GN might be a reliable indicator for the progression of GN. This study indicates that active cellular proliferation is associated with increased actin deposition in glomeruli.

Sex differences in social support, loneliness, and depression among Korean college students

This study examined the sex differences in reports of social support (network size and satisfaction), loneliness, and depression among Korean college students and examined whether measures of social support and loneliness predicted depression scores. In the sample were 452 college students enrolled in four universities in Korea. The women reported a larger social support network size and being less satisfied with their support than the men. Women reported higher scores on the Revised UCLA Loneliness Scale and the Beck Depression Inventory than men. Social support satisfaction scores and network size on the Social Support Questionnaire-6 and scores on the Loneliness Scale predicted scores on Depression in both the groups. Loneliness was the largest predictor of Depression for either sex. The amount of variance in Depression accounted for by Loneliness was 35% for women and 24% for men.

CD8 T cell-mediated rejection of intestinal allografts is resistant to inhibition of the CD40/CD154 costimulatory pathway

BACKGROUND

Disruption of the CD40/CD154 pathway inhibits rejection in numerous models. The importance of this pathway on intestinal allograft rejection was examined in this study.

METHODS

Intestinal grafts from B6C3F1 mice transplanted into C57BL/6 recipients were assessed histologically for rejection.

RESULTS

The monoclonal antibody to CD154, MR1, failed to inhibit rejection in wild-type mice. Similarly, CD154-/- recipient mice rejected intestinal allografts. MR1 did inhibit early rejection in CD8-/- mice, but had no effect in CD4-/- recipients. All MR1-treated CD8-/- recipients eventually developed rejection. No benefit was observed when blockade of the CD40/CD154 pathway by MR1 was combined with blockade of the CD28/B7 pathway by mCTLA4Ig.

CONCLUSIONS

These data suggest that CD4+ T cells mediating intestinal allograft rejection may be more dependent upon the CD40/CD154 pathway than CD8+ T cells. This finding highlights the importance of identifying agents that suppress CD8+ T cell-mediated rejection.

Regulation of the PH-domain-containing tyrosine kinase Etk by focal adhesion kinase through the FERM domain

Etk/BMX, a member of the Btk family of tyrosine kinases, is highly expressed in cells with great migratory potential, including endothelial cells and metastatic carcinoma cell lines. Here, we present evidence that Etk is involved in integrin signalling and promotes cell migration. The activation of Etk by extracellular matrix proteins is regulated by FAK through an interaction between the PH domain of Etk and the FERM domain of FAK. The lack of Etk activation by extracellular matrix in FAK-null cells could be restored by co-transfection with wild-type FAK. Disrupting the interaction between Etk and FAK diminished the cell migration promoted by either kinase. Furthermore, inhibiting Etk expression in metastatic carcinoma cell lines with an antisense oligonucleotide blocks integrin-mediated migration of these cells. Taken together, our data indicate the essential role of the interaction of the PH domain of Etk and the FERM domain of FAK in integrin signalling.

Different mechanisms of cardiac allograft rejection in wildtype and CD28-deficient mice

Although CD28 blockade results in long-term cardiac allograft survival in wildtype mice, CD28-deficient mice effectively reject heart allografts. This study compared the mechanisms of allogeneic responses in wildtype and CD28-deficient mice. Adoptive transfer of purified CD28-deficient T cells into transplanted nude mice resulted in graft rejection. However, this model demonstrated that the allogeneic T cell function was severely impaired when compared with wildtype T cells, despite similar survival kinetics. Cardiac allograft rejection depended on both CD4+ and CD8+ T cell subsets in CD28-deficient mice, whereas only CD4+ T cells were necessary in wildtype recipients. These results suggested that CD8+ T cells were more important in CD28-deficient than wildtype mice. In addition to the CD8+ T cell requirement, allograft rejection in CD28-deficient mice was dependent on a sustained presence of CD4+ T cells, whereas it only required the initial presence of CD4+ T cells in wildtype mice. Taken together, these data suggest that CD4+ T cells from CD28-deficient mice have impaired responses to alloantigen in vivo, thus requiring long-lasting cooperation with CD8+ T cell responses to facilitate graft rejection. These results may help to explain the failure to promote graft tolerance in some preclinical and clinical settings.

Regulatory and effector CD4 T cells in nonobese diabetic mice recognize overlapping determinants on glutamic acid decarboxylase and use distinct V beta genes

The 524--543 region of glutamic acid decarboxylase (GAD65), GAD65(524--543), is one of the first fragments of this islet Ag to induce proliferative T cell responses in the nonobese diabetic (NOD) mouse model of spontaneous autoimmune diabetes. Furthermore, NOD mice given tolerogenic doses of GAD65(524--543) are protected from spontaneous and cyclophosphamide-induced diabetes. In this study, we report that there are at least two I-A(g7)-restricted determinants present in the GAD65(524--543) sequence, each capable of recruiting unique T cell repertoires characterized by distinct TCR V beta gene use. CD4(+) T cells arise spontaneously in young NOD mice to an apparently dominant determinant found within the GAD65 peptide 530--543 (p530); however, T cells to the overlapping determinant 524-538 (p524) dominate the response only after immunization with GAD65(524--543). All p530-responsive T cells used the V beta 4 gene, whereas the V beta 12 gene is preferentially used to encode the TCR of p524-responsive T cell populations. T cell clones and hybridomas from both of these T cell groups were responsive to APC pulsed with GAD65(524--543) or whole rGAD65. p524-reactive cells appeared to be regulatory upon adoptive transfer into young NOD mice and could inhibit insulin-dependent diabetes mellitus development, although they were unable to produce IL-4, IL-10, or TGF beta upon antigenic challenge. Furthermore, we found that i.p. injection with p524/IFA was very effective in providing protection from cyclophosphamide-induced insulin-dependent diabetes mellitus. These data demonstrate that the regulatory T cells elicited by immunizing with GAD65(524--543) are unique and distinct from those that arise from spontaneous endogenous priming, and that T cells to this limited region of GAD65 may be either regulatory or pathogenic.

Role of STAT4 and STAT6 signaling in allograft rejection and CTLA4-Ig-mediated tolerance

STAT4(-/-) mice have impaired type 1 T cell differentiation, whereas STAT6(-/-) mice fail to generate type 2 responses. The role of type 1 and type 2 T cell differentiation in acute cardiac allograft rejection and in the induction of tolerance was examined in wild-type, STAT4(-/-), and STAT6(-/-) recipients. All recipients rejected the grafts promptly. Analysis of in situ cytokine gene expression in the allografts confirmed decreased levels of IFN-gamma in STAT4(-/-) recipients and undetectable levels of IL-4 and IL-5 in STAT6(-/-) mice. Blockade of the CD28/B7 costimulatory pathway prolonged cardiac graft survival for >100 days in 100% of wild-type and STAT4(-/-) mice. However, 14% of CTLA4-Ig-treated STAT6(-/-) mice rejected their grafts between 20 and 100 days. Moreover, of those animals followed past 100 days, 60% of the STAT6(-/-) mice rejected their grafts. Splenocytes harvested on day 145 posttransplant from CTLA4-Ig-treated rejecting STAT6(-/-) recipients were transfused into syngeneic SCID mice transplanted with donor or third party cardiac allografts. Both donor and third party grafts were rejected, indicating that the initial graft loss may be due to an immunological rejection. In contrast, when splenocytes from CTLA4-Ig-treated wild-type or nonrejecting STAT6(-/-) mice were transferred into SCID recipients, donor allografts were accepted, but third party hearts were rejected. Thus, long-term prolongation of cardiac allograft survival by CTLA4-Ig is STAT4-independent but, at least in part, STAT6-dependent. These data suggest that the balance of type 1 and type 2 T lymphocyte differentiation is not critical for acute rejection but influences the robust tolerance induced by CD28/B7 blockade in this model.

Seroprevalence of porcine respiratory coronavirus in selected Korean pigs

A total of 446 serum samples from 88 herds in Korea were examined for antibody to porcine respiratory coronavirus (PRCV) using blocking enzyme-linked immunosorbent assay (ELISA). All serum samples were collected from 24- to 26-week-old finishing pigs between December 1998 and June 1999. By ELISA, 237 out of 446 sera tested (53.1%) and 54 out of 88 sampled herds (61.3%) were positive against PRCV. Of 446 sera from 88 herd tested, 185 (41.5%) serum samples from 22 (25%) herds were seronegative against PRCV and transmissible gastroenteritis virus infection. Our data suggested that seropositive herds for PRCV are distributed diffusely throughout South Korea.

Molecular characterization of Vibrio parahaemolyticus vSGLT: a model for sodium-coupled sugar cotransporters

The Na(+)/galactose cotransporter (vSGLT) of Vibrio parahaemolyticus, tagged with C-terminal hexahistidine, has been purified to apparent homogeneity by Ni(2+) affinity chromatography and gel filtration. Resequencing the vSGLT gene identified an important correction: the N terminus constitutes an additional 13 functionally essential residues. The mass of His-tagged vSGLT expressed under its native promoter, as determined by electrospray ionization-mass spectrometry (ESI-MS), verifies these 13 residues in wild-type vSGLT. A fusion protein of vSGLT and green fluorescent protein, comprising a mass of over 90 kDa, was also successfully analyzed by ESI-MS. Reconstitution of purified vSGLT yields proteoliposomes active in Na(+)-dependent galactose uptake, with sugar preferences (galactose > glucose > fucose) reflecting those of wild-type vSGLT in vivo. Substrates are transported with apparent 1:1 stoichiometry and apparent K(m) values of 129 mm (Na(+)) and 158 microm (galactose). Freeze-fracture electron microscopy of functional proteoliposomes shows intramembrane particles of a size consistent with vSGLT existing as a monomer. We conclude that vSGLT is a suitable model for the study of sugar cotransporter mechanisms and structure, with potential applicability to the larger SGLT family of important sodium:solute cotransporters. It is further demonstrated that ESI-MS is a powerful tool for the study of proteomics of membrane transporters.

Transmissible gastroenteritis virus induces apoptosis in swine testicular cell lines but not in intestinal enterocytes

Evidence of apoptosis caused by infection with the Purdue strain of transmissible gastroenteritis virus (TGEV) was sought in vitro (in infected swine testicular [ST] cells) and in vivo (in the intestinal tissues of infected piglets). The methods used were (1) DNA electrophoresis for detection of DNA fragmentation, and (2) terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-fluorescein nick and labelling (TUNEL). DNA "laddering" was detected in TGEV-infected ST cells only. Numerous signs of apoptosis were detected in TGEV-infected ST cells by TUNEL assay, the positive (dark brown) staining reaction being present in the majority of cell nuclei, without background staining. No such staining was seen in TGEV-infected enterocytes at various times after inoculation of piglets. Thus, it would appear that apoptosis does not occur in the enterocytes of piglets infected with TGEV.

Detection and differentiation of porcine epidemic diarrhoea virus and transmissible gastroenteritis virus in clinical samples by multiplex RT-PCR

A multiplex reverse-transcriptase-PCR (RT-PCR) procedure was developed for the simultaneous detection of porcine epidemic diarrhoea virus (PEDV) and transmissible gastroenteritis virus (TGEV) in preweaning pigs with diarrhoea. The membrane gene of PEDV and the nucleocapsid gene of TGEV were chosen as targets. The PCR products of PEDV and TGEV had molecular sizes of 412 and 612 base pairs, respectively. Primers from PEDV did not react with any TGEV tested and vice versa. In addition, the primers did not react with other pig viruses. The multiplex RT-PCR was able to detect 10 tissue culture-infective doses 50 per cent (TCID50)/ml of PEDV or TGEV with each of the primer sets for PEDV and TGEV, respectively. The RNAS of PEDV and TGEV were detected directly in intestinal and faecal samples from pigs infected experimentally with either virus. The results of the assay correlated well with the results of virus isolation. None of the five control specimens was positive. PEDV was detected in 10 intestinal and nine faecal samples, and among the nine positive faecal samples two were culture-negative. TGEV was also detected in 10 intestinal and nine faecal samples, and among the nine positive faecal samples, three were culture-negative.

Absence of host B7 expression is sufficient for long-term murine vascularized heart allograft survival

CD28 antagonists have been shown to promote long-term graft survival and induce donor-specific tolerance. In this study, the role of CD28/B7 costimulation and the relative importance of host versus donor B7 expression in allograft rejection was assessed in a murine abdominal vascularized heterotopic heart transplant model. Wild-type, CD28-deficient, or B7-1/B7-2-deficient C57BL/6 (B6) mice were grafted with allogeneic wild type or B7-1/B7-2-deficient hearts. The results demonstrate allogeneic heart grafts survive long-term in mCTLA4Ig-treated B6 and untreated B7-1/B7-2-deficient B6 recipients but not CD28KO B6 mice. B7-1/B7-2KO B6 recipients treated with anti-CD28 (PV-1) or recombinant human IL-2 rejected the heart transplants indicating that these mice are immunologically competent to reject grafts if costimulatory signals are supplied or bypassed. Finally, there was no difference in rejection between normal animals transplanted with wild-type versus B7-1/B7-2-deficient hearts. These results support a critical role for B7-expressing host antigen presenting cells in the rejection of heart allografts in mice and differences among B7KO and CD28KO animals.

In situ hybridization for the detection and localization of porcine epidemic diarrhea virus in the intestinal tissues from naturally infected piglets

Detection and localization of porcine epidemic diarrhea virus (PEDV) was studied by in situ hybridization with a nonradioactive digoxigenin-labeled probe in formalin-fixed, paraffin-embedded tissues from 10 naturally infected piglets. A 377-base pair cDNA probe for viral RNA encoding the membrane proteins of PEDV cell-culture-adapted strain V215/78 was generated by the reverse transcription polymerase chain reaction. In the retrospective study of pigs from herds with diarrhea, the 10 piglets naturally infected with PEDV had positive signals for PEDV by in situ hybridization. When intestinal tissues were hybridized with the PEDV probe, a strong signal was seen in the villus enterocytes of jejunum and ileum but not in the cecum and colon. Positive cells typically had dark brown reaction products in the cytoplasm. Scattered epithelial cells along the ileal Peyer's patches dome areas contained viral RNA. In one piglet, hybridization signal was also found in the duodenum. PEDV was not demonstrated in tissues outside of the intestinal tract. These findings indicate that jejunal and ileal villus enterocytes are the main target of PEDV replication during epizootic outbreaks of the disease.

Indoor air quality at the Correr Museum, Venice, Italy

Two multidisciplinary field surveys, one in winter and the other in summer have monitored the indoor microclimate, air pollution, deposition and origin of the suspended particulate matter and microorganisms of the Correr Museum, Venice. In addition, this study was focused to identify the problems caused by the heating and air conditioning system (HAC) and the effects due to the presence of carpets. Heating and air conditioning systems (HACs), when chiefly designed for human welfare, are not suitable for conservation and can cause dangerous temperature and humidity fluctuations. Improvements at the Correr Museum have been achieved with the assistance of environmental monitoring. The carpet has a negative influence as it retains particles and bacteria which are resuspended each time people walk on it. The indoor/outdoor pollutants ratio is greater in the summertime, when doors and windows are more frequently open to allow for better ventilation, illustrating that this ratio is mainly governed by the free exchange of the air masses. The chemical composition, size and origin of the suspended particulate matter have been identified, as well as the bacteria potentially dangerous to the paintings. Some general suggestions for improving indoor air quality are reported in the conclusions.

Monoclonal antibody-based immunohistochemical detection of porcine epidemic diarrhea virus antigen in formalin-fixed, paraffin-embedded intestinal tissues

An immunohistochemistry technique was developed for the diagnosis of porcine epidemic diarrhea virus (PEDV). The technique was tested on formalin-fixed, paraffin-embedded intestinal tissues from piglets naturally infected with PEDV. Five different monoclonal antibodies (MAbs) were tested in this study. PEDV antigen was consistently detected in the PLP (4% paraformaldehyde, 100 mM L-lysine dihydrochloride, 10 mM sodium m-periodate in phosphate-buffered saline)-fixed PEDV-infected Vero cells or formalin-fixed, paraffin-embedded intestinal tissues from piglets naturally infected with PEDV. The C9-2-2 MAb gave the strongest reactivity and least background staining, detecting 10 of 10 infected pigs. The positive reaction was cytoplasmic. Positive enterocytes were distributed over the tip and along the sides of atrophied or fused villi in the jejunum and ileum. Positive-staining cells were not detected in the crypts. No staining was observed in cecum and colon. No positive cells were observed when the C9-2-2 MAb was reacted with the tissue sections from noninfected piglets or from transmissible gastroenteritus virus (TGEV)- and rotavirus-infected piglets. The selected anti-PEDV MAbs tested on formalin-fixed, paraffin-embedded tissue sections are useful for diagnosis when virus isolation is not available. This method would be of particular value in countries where both PEDV and TGEV are epizootic and would aid in differentiating between PEDV and TGEV infection.

Cutting edge: blockade of the CD28/B7 costimulatory pathway inhibits intestinal allograft rejection mediated by CD4+ but not CD8+ T cells

The effect of blocking the CD28/B7 costimulatory pathway on intestinal allograft rejection was examined in mice. Murine CTLA4Ig failed to prevent the rejection of allografts transplanted into wild-type or CD4 knockout (KO) mice but did inhibit allograft rejection by CD8 KO recipients. This effect was associated with decreased intragraft mRNA for IFN-gamma and TNF-alpha and increased mRNA for IL-4 and IL-5. This altered pattern of cytokine production was not observed in allografts from murine CTLA4Ig-treated CD4 KO mice. These data demonstrate that blockade of the CD28/B7 pathway has different effects on intestinal allograft rejection mediated by CD4+ and CD8+ T cells and suggest that these T cell subsets have different costimulatory requirements in vivo. The results also suggest that the inhibition of CD4+ T cell-mediated allograft rejection by CTLA4Ig may be related to down-regulation of Th1 cytokines and/or up-regulation of Th2 cytokines.

The indoor environment of a modern museum building, the Sainsbury Centre for Visual Arts, Norwich, UK

A multi-disciplinary approach was used to investigate the indoor environment of a modern museum building, and its suitability for the conservation of the collection therein. Climate, gaseous and particulate pollution and the concentrations of bacteria were measured in summer and winter campaigns. While the environment overall was found to be an acceptable one, a number of drawbacks were highlighted, the most serious of these being the large temperature and humidity fluctuations that occurred in the summer.

Predictors of loneliness in elderly Korean immigrant women living in the United States of America

The purpose of this study was to examine the predictors of loneliness in elderly Korean immigrant women. The sample was derived from a larger study designed to examine loneliness in elderly Korean immigrants. Subjects were 110 elderly Korean immigrant women who were at least 60 years of age and lived in a large metropolitan city area in the United States of America. Data were collected by telephone interview using the Revised University of California Los Angeles (UCLA) Loneliness Scale (RULS), Social Support Questionnaire, Ethnic Attachment Questionnaire and Instrumental Activities of Daily Living (ADL) Scale. Measures were prepared using translation and back-translation procedures. Results indicate that elderly Korean immigrant women were more lonely than those found in other studies. Satisfaction with social support, social network size, ethnic attachment and functional status were predictive variables of loneliness. Satisfaction with social support was the largest predictor of loneliness in elderly Korean women. Marital status was not a predictor of loneliness.