Individual studies have suggested the utility of fractional exhaled nitric oxide (FeNO) measurement in detecting cough-variant asthma and eosinophilic bronchitis in patients with chronic cough. The aim of this study was to clarify a correlation of cough reflex sensitivity and fractional exhaled nitric oxide in asthmatic children. 25 children with asthma and 15 controls were submitted to cough reflex sensitivity measurement – capsaicin aerosol in doubling concentrations (from 0.61 to 1250 µmol/l) was inhaled by a single breath method. Concentrations of capsaicin causing two (C2) and five coughs (C5) were reported. Fractional exhaled nitric oxide (FeNO) measurement was included. Asthmatic children (11 boys and 14 girls, mean age 9±1 years) and control group (unconfirmed diagnosis of asthma) (6 boys and 9 girls, mean age 8±1 years) were included into the study. FeNO vs. C2 in asthma (Spearman´s rank correlation: -0.146, p=0.49); FENO vs. C5 in asthma (Spearman´s rank correlation: -0.777, p=0.71). We found that there is no correlation between cough reflex sensitivity and fractional exhaled nitric oxide either in children with asthma or in the control group.
New knowledge about the neural aspects of cough has revealed
a complex network of pathways that initiate cough. The effect of
inflammation on cough neural processing occurs at multiple
peripheral and central sites within the nervous system. Evidence
exists that direct or indirect neuroimmune interaction induces
a complex response, which can be altered by mediators released
by the sensory or parasympathetic neurons and vice versa. The
aim of this study was to clarify changes of cough reflex sensitivity
– the activity of airway afferent nerve endings - in asthmatic
children. 25 children with asthma and 15 controls were submitted
to cough reflex sensitivity measurement - capsaicin aerosol in
doubling concentrations (from 0.61 to 1250 µmol/l) was inhaled
by a single breath method. Concentrations of capsaicin causing
two (C2) and five coughs (C5) were reported. Asthmatic children'
(11 boys and 14 girls, mean age 9 ± 1 yrs) cough reflex sensitivity
(geometric mean, with the 95 % CI) for C2 was 4.25 (2.25-8.03)
µmol/l vs. control C2 (6 boys and 9 girls, mean age 8 ± 1 yrs) was
10.61 (5.28-21.32) µmol/l (p=0.024). Asthmatic children' C5 was
100.27 (49.30-203.93) µmol/l vs. control C5 56.53 (19.69-162.35)
µmol/l (p=0.348). There was a statistically significant decrease of
C2 (cough threshold) in the asthmatic patients relative to controls
(p-value for the two-sample t-test of log(C2) for the one-sided
alternative, p-value = 0.024). The 95 % confidence interval for the
difference of the mean C2 in asthma vs. control, [1.004, 6.207].
For C5, the difference was not statistically significant (p-value =
0.348). There was a statistically significant decrease of cough
reflex sensitivity (the activity of airway afferent nerve endings) -
C2 value in the asthmatic children relative to controls.
Increasing evidence points to host genetics as a factor in COVID19 prevalence and outcome. CCR5 is a receptor for proinflammatory chemokines that are involved in host responses, especially to viruses. The CCR5 Δ32 minor allele is an interesting variant, given the role of CCR5 in some viral infections, particularly HIV-1. Recent studies of the impact of CCR5-Δ32 on COVID-19 risk and severity have yielded contradictory results. This ecologic study shows that the CCR5-Δ32 allelic frequency in a European population was significantly negatively correlated with the number of COVID-19 cases (p=0.035) and deaths (p=0.006) during the second pandemic wave. These results suggest that CCR5-Δ32 may be protective against SARS-CoV-2 infection, as it is against HIV infection, and could be predictive of COVID-19 risk and severity. Further studies based on samples from populations of different genetic backgrounds are needed to validate these statistically obtained findings.
In the present study, the effect of polycyclic musk compound tonalide (AHTN) in two concentrations was studied in male rainbow trout (Oncorhynchus mykiss, Walbaum 1792). A feeding trial was conducted with AHTN incorporated into feed granules. One concentration was environmentally relevant (854 µg/kg); the second one was 10× higher (8699 µg/kg). The fish were fed twice a day with the amount of feed at 1 % of their body weight. After an acclimatization period, the experimental phase in duration of six weeks followed. At the end of the experiment, fish were sampled and the biometrical data were recorded. Subsequently, hematological and biochemical tests, histopathological examination, analysis of oxidative stress markers and evaluation of endocrine disruption using plasma vitellogenin were performed. In conclusion, an increase of hematocrit for both AHTN concentrations was found, but no significant changes were observed in biochemical profile. Moreover, AHTN caused lipid peroxidation in caudal kidney tissue, which was confirmed by histopathological images. The long-lasting AHTN exposure could thus be harmful for maintaining homeostasis in the rainbow trout organism. However, the vitellogenin concentration seemed not to be affected by AHTN.
The SARS-CoV-2 pandemic has indeed been one of the most significant problems facing the world in the last decade. It has affected (directly or indirectly) the entire population and all age groups. Children have accounted for 1.7 % to 2 % of the diagnosed cases of COVID-19. COVID-19 in children is usually associated with a mild course of the disease and a better survival rate than in adults. In this review, we investigate the different mechanisms which underlie this observation. Generally, we can say that the innate immune response of children is strong because they have a trained immunity, allowing the early control of infection at the site of entry. Suppressed adaptive immunity and a dysfunctional innate immune response is seen in adult patients with severe infections but not in children. This may relate to immunosenescence in the elderly. Another proposed factor is the different receptors for SARS-CoV-2 and their differences in expression between these age groups. In infants and toddlers, effective immune response to viral particles can be modulated by the pre-existing non-specific effect of live attenuated vaccines on innate immunity and vitamin D prophylaxis. However, all the proposed mechanisms require verification in larger cohorts of patients. Our knowledge about SARS-CoV-2 is still developing.
A close interaction between the virus SARS-CoV-2 and the
immune system of an individual results in a diverse clinical
manifestation of the COVID-19 disease. While adaptive immune
responses are essential for SARS-CoV-2 virus clearance, the
innate immune cells, such as macrophages, may contribute, in
some cases, to the disease progression. Macrophages have
shown a significant production of IL-6, suggesting they may
contribute to the excessive inflammation in COVID-19 disease.
Macrophage Activation Syndrome may further explain the high
serum levels of CRP, which are normally lacking in viral
infections. In adaptive immune responses, it has been revealed
that cytotoxic CD8+ T cells exhibit functional exhaustion patterns,
such as the expression of NKG2A, PD-1, and TIM-3. Since SARSCoV-2 restrains antigen presentation by downregulating
MHC class I and II molecules and, therefore, inhibits the T cellmediated immune responses, humoral immune responses also
play a substantial role. Specific IgA response appears to be
stronger and more persistent than the IgM response. Moreover,
IgM and IgG antibodies show similar dynamics in COVID-19
disease.
Knowledge of genomic interindividual variability could help us to explain why different manifestation of clinical severity of Covid-19 infection as well as modified pharmacogenetic relations can be expected during this pandemic condition.
Few peculiarities have been observed in the etiology of coronavirus disease 2019 (COVID-19), one such being its greater prevalence in men than women partly due to the higher expressions of angiotensin-converting enzyme-2 (ACE2) in the male reproductive tissues. Recent scientific reports are in line with some of the evidence-based hypotheses in the initial phase of the COVID-19 pandemic, regarding the involvement of oxidative stress (OS) and oxidant-sensitive pathways in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection-mediated male reproductive disruptions. The seminal dissemination of SARS-CoV-2 or its components, testicular disruptions due to viral infection and oxidative damage in the testis have all been evidenced recently. High-dose of antioxidants, such as vitamin C, have been shown to be a useful treatment for COVID-19 patients, to alleviate systemic inflammation and OS. In addition, vitamin C is a major testicular antioxidant that neutralizes excess reactive oxygen species (ROS), prevents sperm agglutination, prevents lipid peroxidation, recycles vitamin E, and protects against DNA damage. Thus, the present review aims to discuss the mechanism of COVID-19- mediated male reproductive dysfunctions, based on the evidence available so far, and explore the possibility of using vitamin C in alleviating testicular OS and associated damage caused by COVID-19.
Strong tolerance of freezing is an important strategy for insects living in extremely cold regions. They produce highly effective cryoprotectant systems consisting of ice-nucleating proteins and polyols, which enables tolerable freezing of the body fluid. Therefore, the measurement of the concentrations of polyols and the activity of ice nucleators in the haemolymph is an essential tool for describing tolerance to ice formation in insects occurring in particularly cold places. This study evaluates three parameters: insect body supercooling point (SCP), haemolymph glycerol content and the profile of haemolymph ice nucleating activity that characterize the strategies of cold adaptation and cold hardiness in two previously unstudied beetles, Chrysolina graminis graminis L. and Galerucella nymphaea L., inhabiting Yakutia (Russian Far East, latitude 62°N). The high SCP values, ice nucleating activity and survival of the chrysomelids after freezing indicate that both species are tolerant of freezing. According to the profiles of ice-nucleating activity, the haemolymph from C. graminis graminis is characterized by a higher nucleating potential than that from G. nymphaea. The glycerol level is also higher in C. graminis graminis. The results indicate that both species develop tolerance to low temperatures, but the cold hardiness potential of C. graminis graminis is greater than that of G. nymphaea. This was revealed by the survival test, in which beetles were frozen to a temperature of -22°C for 30 min; 86% of C. graminis graminis and 72% of G. nymphaea survived the test. Thus, the freeze-tolerance of these beetles seems to be based on the production of an integrated cryoprotectant system, the quality of which apparently influences the range of their cold resistance., Natalia G. Li., and Obsahuje bibliografii
In some regions of Argentina and Brazil, the South American fruit fly Anastrepha fraterculus (Wied.) (Diptera: Tephritidae) causes significant damage to crops. An efficient integrated management program requires knowledge of pest population dynamics, dispersion patterns, sexual and oviposition behaviour, and adaptive landscape. The present study combined simple sequence repeat (SSR) molecular markers and morphometric datasets in order to analyse the population structure and infer the oviposition resource use strategy of the females. Infested guava fruits were collected from nine wild trees in Tucumán, Argentina, and a total of 140 adult A. fraterculus were recovered. These were then measured for six morphometric traits and 89 of them were genotyped for eight SSR loci. Genetic variability estimates were high (expected heterozygosity = 0.71, allelic richness = 12.5), with 8 to 20 alleles per locus. According to Wright's F-statistics estimates, the highest proportion (83%) of genetic variation occurred within individuals while variance between and within fruits were similar (≈ 8.5%). Analysis of the cryptic genetic structure based on SSR using different approaches, namely discriminant analysis of principal components (DAPC) and sparse non-negative matrix factorization (SNMF), yielded results consistent with the occurrence of two clusters with virtually no admixture. Average kinship between individuals which had emerged from the same fruit (0.07) was lower than that expected for full-sib families. Univariate and multivariate analyses of phenotypic data showed 54-66% of variance among individuals within fruits and 34-46% among fruits. The comparison between phenotypic (PST) and molecular (FST) differentiation identified wing width and length as possible target of positive selection. The average kinship and high genetic variation within fruits, together with the highly significant genetic differentiation among fruits, supports the hypothesis that each fruit was colonised by about three ovipositing females. The results also indicate that females were able to disperse widely from the emergence site before mating and starting oviposition activity.