IL-6 and other biomarkers as predictors of severity in COVID-19.

OBJECTIVE: Cytokine release syndrome is suggested to be the most important mechanism triggering acute respiratory distress syndrome and end organ damage in COVID-19. The severity of disease may be measured by different biomarkers. METHODS: We studied markers of inflammation and coagulation as recorded in 29 patients on admission to the hospital in order to identify markers of severe COVID-19 and need of ICU. RESULTS: Patients who were eventually admitted to ICU displayed significantly higher serum levels of interleukin-6 (IL-6), C-reactive protein (CRP), and procalcitonin. No statistical differences were found between the groups in median levels of lymphocytes, D-dimer or ferritin. CONCLUSIONS: IL-6 and CRP were the strongest predictors of severity in hospitalized patients with COVID-19.

A European multicentre evaluation of detection and typing methods for human enteroviruses and parechoviruses using RNA transcripts.

Polymerase chain reaction (PCR) detection has become the gold standard for diagnosis and typing of enterovirus (EV) and human parechovirus (HPeV) infections. Its effectiveness depends critically on using the appropriate sample types and high assay sensitivity as viral loads in cerebrospinal fluid samples from meningitis and sepsis clinical presentation can be extremely low. This study evaluated the sensitivity and specificity of currently used commercial and in-house diagnostic and typing assays. Accurately quantified RNA transcript controls were distributed to 27 diagnostic and 12 reference laboratories in 17 European countries for blinded testing. Transcripts represented the four human EV species (EV-A71, echovirus 30, coxsackie A virus 21, and EV-D68), HPeV3, and specificity controls. Reported results from 48 in-house and 15 commercial assays showed 98% detection frequencies of high copy (1000 RNA copies/5 µL) transcripts. In-house assays showed significantly greater detection frequencies of the low copy (10 copies/5 µL) EV and HPeV transcripts (81% and 86%, respectively) compared with commercial assays (56%, 50%; P = 7 × 10-5 ). EV-specific PCRs showed low cross-reactivity with human rhinovirus C (3 of 42 tests) and infrequent positivity in the negative control (2 of 63 tests). Most or all high copy EV and HPeV controls were successfully typed (88%, 100%) by reference laboratories, but showed reduced effectiveness for low copy controls (41%, 67%). Stabilized RNA transcripts provide an effective, logistically simple and inexpensive reagent for evaluation of diagnostic assay performance. The study provides reassurance of the performance of the many in-house assay formats used across Europe. However, it identified often substantially reduced sensitivities of commercial assays often used as point-of-care tests.

Atopic asthma after rhinovirus-induced wheezing is associated with DNA methylation change in the SMAD3 gene promoter.

Children with rhinovirus-induced severe early wheezing have an increased risk of developing asthma later in life. The exact molecular mechanisms for this association are still mostly unknown. To identify potential changes in the transcriptional and epigenetic regulation in rhinovirus-associated atopic or nonatopic asthma, we analyzed a cohort of 5-year-old children (n = 45) according to the virus etiology of the first severe wheezing episode at the mean age of 13 months and to 5-year asthma outcome. The development of atopic asthma in children with early rhinovirus-induced wheezing was associated with DNA methylation changes at several genomic sites in chromosomal regions previously linked to asthma. The strongest changes in atopic asthma were detected in the promoter region of SMAD3 gene at chr 15q22.33 and introns of DDO/METTL24 genes at 6q21. These changes were validated to be present also at the average age of 8 years.

Soluble ST2 regulation by rhinovirus and 25(OH)-vitamin D3 in the blood of asthmatic children.

Paediatric asthma exacerbations are often caused by rhinovirus (RV). Moreover, 25(OH)-vitamin D3 (VitD3) deficiency during infancy was found associated with asthma. Here, we investigated the innate immune responses to RV and their possible modulation by 25(OH)-VitD3 serum levels in a preschool cohort of children with and without asthma. The innate lymphoid cell type 2 (ILC2)-associated marker, ST2, was found up-regulated in the blood cells of asthmatic children with low serum levels of 25(OH)-VitD3 in the absence of RV in their airways. Furthermore, in blood cells from control and asthmatic children with RV in their airways, soluble (s) ST2 (sST2) protein was found reduced. Asthmatic children with low 25(OH)-VitD3 in serum and with RV in vivo in their airways at the time of the analysis had the lowest sST2 protein levels in the peripheral blood compared to control children without RV and high levels of 25(OH)-VitD3. Amphiregulin (AREG), another ILC2-associated marker, was found induced in the control children with RV in their airways and low serum levels of 25(OH)-VitD3. In conclusion, the anti-inflammatory soluble form of ST2, also known as sST2, in serum correlated directly with interleukin (IL)-33 in the airways of asthmatic children. Furthermore, RV colonization in the airways and low serum levels of 25(OH)-VitD3 were found to be associated with down-regulation of sST2 in serum in paediatric asthma. These data indicate a counter-regulatory role of 25(OH)-VitD3 on RV-induced down-regulation of serum sST2 in paediatric asthma, which is relevant for the therapy of this disease.

Clinical and socioeconomic impact of moderate-to-severe versus mild influenza in children.

Some studies have assessed the efficacy of influenza vaccination in children separately for moderate-to-severe and any influenza, but the definition used for identifying children with moderate-to-severe illness has not been validated. We analyzed clinical and socioeconomic data from two prospective cohort studies of respiratory infections among children aged ≤13 years (four influenza seasons, 3,416 child-seasons of follow-up). We categorized children with laboratory-confirmed influenza into two mutually exclusive groups of moderate-to-severe and mild influenza using the previously proposed criteria. We obtained the data for the analyses from structured medical records filled out by the study physicians and from daily symptom cards filled out by the parents. Of 434 cases of influenza, 217 (50 %) were classified as moderate-to-severe and 217 (50 %) as mild. The mean duration of fever was 4.0 days in children with moderate-to-severe influenza and 3.1 days in those with milder illness (P < 0.0001). Antibiotics were prescribed to 111 (51 %) children with moderate-to-severe and to ten (5 %) children with mild influenza (P < 0.0001). The rates of parental work absenteeism were 184 days per 100 children with moderate-to-severe influenza and 135 days per 100 children with mild influenza (P = 0.02). The corresponding rates of children's own absenteeism from day care or school were 297 and 233 days respectively per 100 children (P = 0.006). Categorization of children into groups with moderate-to-severe and mild influenza is meaningful, and it identifies children in whom the clinical and socioeconomic impact of influenza is highest. Illness severity should be considered when assessing influenza vaccine effectiveness in children.

Rhinovirus inhibits IL-17A and the downstream immune responses in allergic asthma.

The proinflammatory cytokine interleukin-17A (IL-17A) is known to mediate antimicrobial activity, but its role during rhinovirus (RV) infections and in asthma needs further investigation. Therefore, we addressed the role of IL-17A during allergic asthma and antiviral immune response in human and murine immunocompetent cells. In this study we found that asthmatic children with a RV infection in their upper airways have upregulated mRNA levels of the antiviral cytokine interferon type I (IFN)-ß and the transcription factor T-box 21 (TBX21) and reduced levels of IL-17A protein in their peripheral blood mononuclear cells (PBMCs). We also found that IL-17A inhibited RV1b replication in infected human lung epithelial cells A549. Furthermore, by using gene array analysis we discovered that targeted deletion of Il17a in murine lung CD4(+) T cells impaired Oas1g mRNA downstream of Ifnß, independently from RV infection. Additionally, in PBMCs of children with a RV infection in their nasalpharyngeal fluid OAS1 gene expression was found downregulated. Finally RV1b inhibited IL-17A production in lung CD4(+) T cells in a setting of experimental asthma. These results indicate that the RV1b inhibits IL-17A in T helper type 17 cells and IL-17A clears RV1b infection in epithelial cells. In both cases IL-17A contributes to fend off RV1b infection by inducing genes downstream of interferon type I pathway.

Distinct regulation of tonsillar immune response in virus infection.

BACKGROUND: The relationships between tonsillar immune responses, and viral infection and allergy are incompletely known. OBJECTIVE: To study intratonsillar/nasopharyngeal virus detections and in vivo expressions of T-cell- and innate immune response-specific cytokines, transcription factors, and type I/II/III interferons in human tonsils. METHODS: Palatine tonsil samples were obtained from 143 elective tonsillectomy patients. Adenovirus, bocavirus-1, coronavirus, enteroviruses, influenza virus, metapneumovirus, parainfluenza virus, rhinovirus, and respiratory syncytial virus were detected using PCR. The mRNA expression levels of IFN-α, IFN-ß, IFN-γ, IL-10, IL-13, IL-17, IL-28, IL-29, IL-37, TGF-ß, FOXP3, GATA3, RORC2, and Tbet were directly analyzed by quantitative RT-PCR. RESULTS: Fifty percentage of subjects reported allergy, 59% had ≥1 nasopharyngeal viruses, and 24% had ≥1 intratonsillar viruses. Tonsillar virus detection showed a strong negative association with age; especially rhinovirus or parainfluenza virus detection showed positive association with IFN-γ and Tbet expressions. IL-37 expression was positively associated with atopic dermatitis, whereas IFN-α, IL-13, IL-28, and Tbet expressions were negatively associated with allergic diseases. Network analyses demonstrated strongly polarized clusters of immune regulatory (IL-10, IL-17, TGF-ß, FOXP3, GATA3, RORC2, Tbet) and antiviral (IFN-α, IFN-ß, IL-28, IL-29) genes. These two clusters became more distinctive in the presence of viral infection or allergy. A negative correlation between antiviral cytokines and IL-10, IL-17, IL-37, FOXP3, and RORC2 was observed only in the presence of viruses, and interestingly, IL-13 strongly correlated with antiviral cytokines. CONCLUSIONS: Tonsillar cytokine expression is closely related to existing viral infections, age, and allergic illnesses and shows distinct clusters between antiviral and immune regulatory genes.

Lower respiratory tract virus findings in mechanically ventilated patients with severe community-acquired pneumonia.

BACKGROUND: The role of viral infections in the etiology of severe community-acquired pneumonia (SCAP) was prospectively evaluated from 2008 to 2012 at a university-level intensive care unit. METHODS: Clinical data and microbiological tests were assessed: blood cultures, urine pneumococcal and legionella antigens, Mycoplasma pneumoniae and Chlamydia pneumoniae antibodies from paired serums, and respiratory virus detection by multiplex, real-time polymerase chain reaction (PCR) from nasopharyngeal swabs and lower tracheal specimens via intubation tube. RESULTS: Of 49 mechanically ventilated SCAP patients (21 men and 28 women; median age, 54 years), the etiology was identified in 45 cases (92%). There were 21 pure bacterial infections (43%), 5 probably pure viral infections (10%), and 19 mixed bacterial-viral infections (39%), resulting in viral etiology in 24 patients (49%). Of 26 viruses, 21 (81%) were detected from bronchial specimens and 5 (19%) from nasopharyngeal swabs. Rhinovirus (15 cases, 58%) and adenovirus (4 cases, 15%) were the most common viral findings. The bacterial-viral etiology group had the highest peak C-reactive protein levels (median, 356 [25th-75th percentiles, 294-416], P = .05), whereas patients with probably viral etiology had the lowest peak procalcitonin levels (1.7 [25th-75th percentiles, 1.6-1.7]). The clinical characteristics of pure bacterial and mixed bacterial-viral etiologies were comparable. Hospital stay was longest among the bacterial group (17 vs 14 days; P = .02). CONCLUSIONS: Viral findings were demonstrated in almost half of the SCAP patients. Clinical characteristics were similar between the pure bacterial and mixed bacterial-viral infections groups. The frequency of viral detection depends on the availability of PCR techniques and lower respiratory specimens.

Human parvoviruses B19, PARV4 and bocavirus in pediatric patients with allogeneic hematopoietic SCT.

Among the immunocompetent, infections with parvovirus B19 (B19V) and human bocavirus (HBoV) 1 range clinically from asymptomatic to severe, while following allogeneic hematopoietic SCT (HSCT) B19V can cause a persistent severe illness. The epidemiology and clinical impact of HBoV1 and the other emerging parvovirus 4 (PARV4) among immunocompromised patients have not been established. To determine the occurrence and clinical spectrum of B19V, PARV4 and HBoV1 infections, we performed a longitudinal molecular surveillance among 53 allogeneic HSCT recipients for pre- and post-HSCT DNAemias of these parvoviruses. Quantitative real-time PCR showed B19V DNA in sera of 16 (30%) patients, at mean levels of 4.6 × 10(3), 9.9 × 10(7), 1.1 × 10(10) and 1.6 × 10(2) B19V DNA copies/mL pre-HSCT (9/53), and at 1 (6/53), 2 (4/53) and 3 months (1/25) post HSCT, respectively. However, no clinical manifestation correlated with the presence of B19V viremia. All B19V sequences were of genotype 1. None of the sera investigated contained PARV4 or HBoV1 DNAs. Our data demonstrate B19V viremia to be frequent among pediatric allogeneic HSCT recipients, yet without apparent clinical correlates. PARV4 or HBoV1 viremias were not seen in these immunocompromised patients.

Increased incidence of Mycoplasma pneumoniae infection in Finland, 2010-2011.

The number of cases of Mycoplasma pneumoniae infection detected by laboratory-based surveillance increased in Finland in late 2010. During 2011, the number of cases was four times higher than during the previous epidemic in 2005. The 2011 epidemic affected mostly school-age children. The increased number of cases was probably not due to changes in laboratory procedures, but public interest may have had an effect, since the number of Google queries followed closely the epidemic curve.

Nasopharyngeal bacterial colonization during the first wheezing episode is associated with longer duration of hospitalization and higher risk of relapse in young children.

The purpose of this study was to examine the association between bacterial colonization/infection and respiratory outcomes in children younger than 3 years old who were hospitalized for their first wheezing episode. This was an observational study. The primary outcome was hospitalization time and the secondary outcomes included relapses within 2 months and time to recurrent wheezing (i.e. three physician confirmed wheezing episodes) within 12 months. Bacterial antibody assays for Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Mycoplasma pneumoniae and Chlamydia pneumoniae were studied as well as nasopharyngeal bacterial culture for the three former and urine pneumococcal antigen. Nasopharyngeal bacterial culture was positive in 31/52 (60%) children, serologic evidence of bacterial infection was found in 17/96 (18%) children, urine pneumococcal antigen was positive in 24/101 (24%), and any bacterial detection method was positive in 53/106 (50%) children. The children with positive nasopharyngeal bacterial culture had longer duration of hospitalization (hazard ratio 2.4) and more often relapsed within two months than those with negative culture (odds ratio 7.3). In this study, half of the first time wheezing children had bacterial colonization or symptomatic or asymptomatic bacterial infection. The bacterial colonization (i.e. positive nasopharyngeal bacterial culture) was associated with longer duration of hospitalization and higher risk of recurrent wheezing.

Allergic sensitization is associated with rhinovirus-, but not other virus-, induced wheezing in children.

BACKGROUND: Data on the link between atopy and viral wheeze are limited. AIM: To evaluate the association between IgE sensitization and viral infection in wheezing children. METHODS: This is an observational study in hospitalized wheezing children (n = 247; median age 1.6 ; interquartile range 1.1, 2.9). Eighteen respiratory viral infections were studied using all available methods. A specific immunoglobulin E (IgE) sensitization for common food and aeroallergens and other atopy-related variables including total IgE, blood and nasal eosinophils, exhaled nitric oxide, eczema and atopic eczema, parental allergy and asthma, number of wheezing episodes, positive asthma predictive index or asthma and use of inhaled corticosteroid were correlated with specific viral etiology. RESULTS: Atopy was closely associated with sole rhinovirus etiology (n = 58) but not with sole respiratory syncytial virus, sole enterovirus, sole human bocavirus, sole other virus, mixed viral, or virus negative etiology. The number of sensitizations was particularly associated with sole rhinovirus etiology (odds ratio 4.59; 95% confidence interval 1.78, 11.8; adjusted to age and sex), followed by aeroallergen sensitization (respectively; 4.18; 2.00, 8.72), total IgE level (2.06; 1.32, 3.21), food allergen sensitization (2.02; 1.08, 3.78), and nasal eosinophil count (1.52; 1.08, 2.13). CONCLUSIONS: According to our data, allergic sensitization is positively linked to rhinovirus-, but not other virus-, associated wheezing and calls attention for studies to test rhinovirus-associated wheezing as a part of asthma risk indices.

Effects of levosimendan in experimental acute coxsackievirus myocarditis.

BACKGROUND: Acute heart failure is a potentially fatal manifestation of viral myocarditis. Development of myocardial damage in myocarditis involves cardiomyocyte apoptosis. Levosimendan is a novel calcium sensitizing inotropic agent with anti-apoptotic properties. We studied the feasibility of inotropic treatment with levosimendan and its effects on apoptosis in experimental acute heart failure caused by coxsackievirus myocarditis. MATERIALS AND METHODS: Adolescent BALB/c mice were infected with myocarditic Woodruff variant of coxsackievirus B3 (2 x 10(4) plaque-forming units). Mice were randomized into those receiving levosimendan 0.33 mg kg(-1) (total dose 1 mg kg(-1) day(-1)) (n = 20) or vehicle (n = 19) given orally by gauge three times a day for 7 days after infection. Left ventricular function was evaluated by transthoracic echocardiography and the mice were euthanized on day 7. Histopathology, amount of virus in the heart (virus titration assay) and cardiomyocyte apoptosis (TUNEL assay) were studied. Uninfected untreated control mice were also studied. RESULTS: Infection resulted in histopathologically severe myocarditis and significant impairment of left ventricular function. Levosimendan treatment significantly improved ventricular function (fractional shortening 0.32 +/- 0.04 vs. 0.23 +/- 0.05, P = 0.005; contractility 0.60 +/- 0.12 vs. 0.39 +/- 0.14, P = 0.007 and myocardial performance index 0.36 +/- 0.06 vs. 0.62 +/- 0.15, P < 0.0001) compared with vehicle. Levosimendan also reduced cardiomyocyte apoptosis (0.26 +/- 0.08% vs. 0.44 +/- 0.15% in vehicle, P = 0.008), but did not have an effect on areas of myocardial necrosis or inflammation, or the amount of virus in the heart. Levosimendan treatment did not affect mortality (total mortality 63%). CONCLUSIONS; Levosimendan improves ventricular function and inhibits cardiomyocyte apoptosis; therefore, it is suggested as a potentially feasible therapy in acute heart failure caused by viral myocarditis.

Development of troponin autoantibodies in experimental coxsackievirus B3 myocarditis.

BACKGROUND: Autoantibodies against various endogenous proteins are found in myocarditis. Troponin autoantibodies are detected in patients with chronic dilated cardiomyopathy, but their presence in myocarditis remains unknown. We set out to study the presence of troponin autoantibodies in experimental viral myocarditis. MATERIALS AND METHODS: BALB/c mice infected with coxsackievirus B3 Nancy strain were followed-up at days 1-7 and 2, 4, 8 and 12 weeks after infection. Levels of circulating cardiac troponin I and circulating troponin autoantibodies were measured. Transthoracic echocardiography was performed. Myocarditis was histopathologically graded and cardiomyocyte apoptosis was quantified (TUNEL). RESULTS: Histopathologically relatively mild acute myocarditis followed by persistent cardiomyocyte damage was observed. Rate of cardiomyocyte apoptosis was the highest on day 5 (0.16 +/- 0.01% vs. 0.03 +/- 0.01% in controls, P < 0.001). Circulating troponin I levels were increased to day 5 (45.2 +/- 6.5 ng mL(-1), P < 0.005 vs. controls). Troponin autoantibodies were detected from 2 weeks after infection (20% of animals had autoantibodies at 2 weeks, 60% at 4 and 8 weeks and 20% at 12 weeks, P < 0.05 vs. controls). Fractional shortening remained decreased after acute myocarditis (0.36 +/- 0.02 at 4 weeks, 0.30 +/- 0.02 at 8 and 12 weeks vs. 0.41 +/- 0.01 before infection, P < 0.01) parallel to development of troponin autoantibodies. CONCLUSION: Troponin autoantibodies are formed in experimental virus induced myocarditis following troponin I release and cardiomyocyte apoptosis. The definite role of these autoantibodies remains to be further characterized.

The cleansing result of oral sodium phosphate is inversely correlated with time between the last administration and colonoscopy.

BACKGROUND: There is some evidence that the timing of sodium phosphate (NaP) ingestion affects the cleansing result. The objective of this study was to evaluate the correlation of cleansing result with the timing of ingestion of NaP. METHODS: 214 consecutive outpatients scheduled to undergo colonoscopy were enrolled in the study. All patients filled out a detailed questionnaire concerning the execution of bowel cleansing. Concomitant with colonoscopy, patient characteristics were recorded and after the procedure the cleansing result was scored. The correlation between cleansing score and time from the last dose of NaP to colonoscopy was evaluated. For further analysis, patients were divided into three groups regarding the time lag from NaP taking to colonoscopy (group 1, 6 h or less; group 2, 6-12 h; group 3, 12 h or more). RESULTS: 204 patients had complete colonoscopy and enough data to be analyzed for the study. The Pearson correlation coefficient for the time between the last dose of NaP and colonoscopy was -0.450 (p=0.0001) showing an inverse correlation. The mean cleansing score (+/-SEM) of group 1 was 4.00+/-0.12, for group 2 it was 3.56+/-0.12, and for group 3 it was 2.64+/-0.14. There were statistically significant differences between all groups. CONCLUSION: The cleansing result of NaP is inversely correlated with the time between last dose of NaP and colonoscopy. Colonoscopy should be preferably performed within 12 hours of taking the second dose of NaP.

Bacterial coinfections in children with viral wheezing.

Bacterial coinfections occur in respiratory viral infections, but the attack rates and the clinical profile are not clear. The aim of this study was to determine bacterial coinfections in children hospitalized for acute expiratory wheezing with defined viral etiology. A total of 220 children aged 3 months to 16 years were investigated. The viral etiology of wheezing was confirmed by viral culture, antigen detection, serologic investigation, and/or PCR. Specific antibodies to common respiratory bacteria were measured from acute and convalescent serum samples. All children were examined clinically for acute otitis media, and subgroups of children were examined radiologically for sinusitis and pneumonia. Rhinovirus (32%), respiratory syncytial virus (31%), and enteroviruses (31%) were the most common causative viruses. Serologic evidence of bacterial coinfection was found in 18% of the children. Streptococcus pneumoniae (8%) and Mycoplasma pneumoniae (5%) were the most common causative bacteria. Acute otitis media was diagnosed in 44% of the children. Chest radiographs showed alveolar infiltrates in 10%, and paranasal radiographs and clinical signs showed sinusitis in 17% of the older children studied. Leukocyte counts and serum C-reactive protein levels were low in a great majority of patients. Viral lower respiratory tract infection in children is often associated with bacterial-type upper respiratory tract infections. However, coexisting bacterial lower respiratory tract infections that induce systemic inflammatory response are seldom detected.

Etiology of aseptic meningitis and encephalitis in an adult population.

OBJECTIVE: To investigate the etiology of aseptic meningitis and encephalitis in an adult population using modern microbiologic methods. METHODS: Consecutive patients (ages > or =16) with aseptic meningitis or encephalitis treated in Turku University Hospital, Finland, during 1999 to 2003 were included in the study. Microbiologic tests were performed, including CSF PCR tests for enteroviruses, herpes simplex virus (HSV) 1, HSV-2, and varicella zoster virus (VZV), as well as serum and CSF antibody analysis for these viruses. Antibody testing was also performed for other pathogens commonly involved in neurologic infections. Virus culture was performed on CSF, fecal, and throat swab specimens. RESULTS: Etiology was defined in 95 of 144 (66%) patients with aseptic meningitis. Enteroviruses were the major causative agents (26%), followed by HSV-2 (17% of all, 25% of females) and VZV (8%). Etiology was identified in 15 of 42 (36%) patients with encephalitis, VZV (12%), HSV-1 (9%), and tick-borne encephalitis virus (9%) being the most commonly involved pathogens. Etiologic diagnosis was achieved by PCR in 43% of the patients with meningitis and in 17% of those with encephalitis. CONCLUSIONS: Enteroviruses and HSV-2 are the leading causes of adult aseptic meningitis, and PCR is of diagnostic value. However, in most cases of encephalitis, the etiology remains undefined.

A UV resonance Raman (UVRR) spectroscopic study on the extractable compounds of Scots pine (Pinus sylvestris) wood. Part I: lipophilic compounds.

The wood resin in Scots pine (Pinus sylvestris) stemwood and branch wood were studied using UV resonance Raman (UVRR) spectroscopy. UVRR spectra of the sapwood and heartwood hexane extracts, solid wood samples and model compounds (six resin acids, three fatty acids, a fatty acid ester, sitosterol and sitosterol acetate) were collected using excitation wavelengths of 229, 244 and 257 nm. In addition, visible Raman spectra of the fatty and resin acids were recorded. Resin compositions of heartwood and sapwood hexane extracts were determined using gas chromatography. Raman signals of both conjugated and isolated double bonds of all the model compounds were resonance enhanced by UV excitation. The oleophilic structures showed strong bands in the region of 1660-1630 cm(-1). Distinct structures were enhanced depending on the excitation wavelength. The UVRR spectra of the hexane extracts showed characteristic bands for resin and fatty acids. It was possible to identify certain resin acids from the spectra. UV Raman spectra collected from the solid wood samples containing wood resin showed a band at approximately 1650 cm(-1) due to unsaturated resin components. The Raman signals from extractives in the resin rich branch wood sample gave even more strongly enhanced signals than the aromatic lignin.

A UV resonance Raman (UVRR) spectroscopic study on the extractable compounds in Scots pine (Pinus sylvestris) wood. Part II. Hydrophilic compounds.

Hydrophilic extracts of Scots pine (Pinus sylvestris) heartwood and sapwood and a solid Scots pine knotwood sample were studied by UV resonance Raman spectroscopy (UVRRS). In addition, UVRR spectra of two hydrophilic model compounds (pinosylvin and chrysin) were analysed. UV Raman spectra were collected using 244 and 257 nm excitation wavelengths. The chemical composition of the acetone:water (95:5 v/v) extracts were also determined by gas chromatography. The aromatic and oleophilic structures of pinosylvin and chrysin showed three intense resonance enhanced bands in the spectral region of 1649-1548 cm(-1). Pinosylvin showed also a relatively intense band in the aromatic substitution region at 996 cm(-1). The spectra of the heartwood acetone:water extract showed many bands typical of pinosylvin. In addition, the extract included bands distinctive for resin and fatty acids. The sapwood acetone:water extract showed bands due to oleophilic structures at 1655-1650 cm(-1). The extract probably also contained oligomeric lignans because the UVRR spectra were in parts similar to that of guaiacyl lignin. The characteristic band of pinosylvin (996 cm(-1)) was detected in the UVRR spectrum of the resin rich knotwood. In addition, several other bands typical for wood resin were observed, which indicated that the wood resin in the knotwood was resonance enhanced even more than lignin.

Glutathione depletion and cardiomyocyte apoptosis in viral myocarditis.

BACKGROUND: The course of viral myocarditis is highly variable. Oxidative stress and Bcl-2 family genes may play a role in its pathogenesis by regulating the amount of cardiomyocyte apoptosis. Apoptosis is difficult to detect and quantify in vivo. Therefore, we set to look for indicators of this potentially preventable form of cell death during various phases of experimental murine coxsackievirus B3 myocarditis. METHODS: BALB/c mice were infected with the cardiotropic coxsackievirus B3 variant. Glutathione (HPLC), cardiomyocyte apoptosis (TUNEL and caspase-3 cleavage), Bax and Bcl-X(L) mRNA expression (real time RT-PCR), histopathology and viral replication (plaque assay and real time RT-PCR) were measured from day 3 to day 20 after infection. RESULTS: Infection caused severe myocarditis and led to progressive decrease of plasma glutathione levels. Myocardial mRNA levels of pro-apoptotic Bax and antiapoptotic Bcl-X(L) were significantly increased from day 3 onwards. Bax mRNA and ratio of Bax to Bcl-X(L) correlated with cardiomyocyte apoptosis (r = 0.77, P = < 0.001 and r 0.51, P < 0.01, respectively). Cardiomyocyte apoptosis was highest on day 5, coinciding with a rapid decline in plasma glutathione (r = -0.52, P = 0.003). CONCLUSIONS: Systemic oxidative stress as indicated by decreased plasma glutathione levels coincides with cardiomyocyte apoptosis in experimental coxsackievirus myocarditis. Decreased plasma glutathione levels and changes in cardiac Bax and Bcl-X(L) mRNA expression identify a phase of myocarditis in which the potentially preventable cardiomyocyte apoptosis is mostly observed.