Finite-Time Stability Analysis of Switched Genetic Regulatory Networks

This paper investigates the finite-time stability problem of switching genetic regulatory networks (GRNs) with interval time-varying delays and unbounded continuous distributed delays. Based on the piecewise Lyapunov-Krasovskii functional and the average dwell time method, some new finite-time stability criteria are obtained in the form of linear matrix inequalities (LMIs), which are easy to be confirmed by the Matlab toolbox. The finite-time stability is taken into account in switching genetic regulatory networks for the first time and the average dwell time of the switching signal is obtained. Two numerical examples are presented to illustrate the effectiveness of our results

Epidemiology of Chlamydiaceae in livestock and emerging Chlamydia psittaci infections in chickens

Chlamydiaceae are a family of obligate intracellular Gram-negative bacteria causing disease in man and animals. C. abortus is a major abortigenic agent in ruminants, causing ovine enzootic abortion (OEA). C. psittaci causes respiratory disease (avian chlamydiosis) in birds and psittacosis or parrot-fever in man. In Chapter I, an overview is given of the epidemiology, prevention, treatment and zoonotic risk of Chlamydiaceae infections in Chinese livestock. Differences in risk-factors, such as bio-security measures, and use of diagnostic tests and veterinary practices applied in China are compared to the West. In Chapter II, we examined the occurrence of C. abortus in Belgian ruminants by serology and molecular diagnosis. Sampling herds at n ≥ 10 revealed a seropositive herd status in 14.3% (6/42), 50% (1/2) and 11.6% (11/95) of sheep, goat and cattle herds, respectively. Seroprevalence in one goat herd was 52.9% (9/17), but prevalence in positive sheep and cattle herds was generally limited to only 1 or 2 seropositive animals on 10 to 20 tested animals per herd. Molecular diagnosis on rectal swabs sampled at 3 cattle farms tested all negative for Chlamydiaceae DNA. In Chapter III, part A, we examined the pathogenicity of the well characterized C. psittaci genotype B (CP3) and D (92/1293) strains in experimentally (aerosol) infected SPF chickens. Both strains caused conjunctivitis, rhinitis and dyspnoea. Pharyngeal and cloacal C. psittaci excretion was observed in all infected animals, indicative for systemic dissemination as proven by immunofluorescence staining of frozen tissue sections. Histopathological lesions were present in all infected chickens. However, differences in pathology were observed as genotype D was more virulent than genotype B, creating mortality and more severe clinical signs and lesions. In Chapter III, part B, sera of 30 Belgian and 10 Northern French chicken farms were tested by a C. psittaci MOMP-based ELISA. Ninety-six percent, 93% and 90% of the Belgian broilers, broiler breeders and layers were seropositive. Ninety-one percent of the French broilers were seropositive. In addition, tissues of 5 Belgian and 5 French broiler farms were examined at slaughter. All French farms ware culture positive while C. psittaci was cultured from the lungs of 80% of examined Belgian farms. Chlamydia psittaci infections are apparently emerging in chickens raised in Belgium and Northern France. We could proof Hill-Evans postulates for chicken-derived C. psittaci genotype B and D strains. In Chapter III, part C, we focused on the histopathological lesions caused in experimentally infected SPF chickens. SPF chickens were experimentally infected with C. psittaci strain 10/423 (genotype B), 10/525 (genotype B) or 10/298 (genotype D), which were all isolated from Belgian or French broilers with pneumonia. All strains induced conjunctivitis, rhinitis, sinusitis, tracheitis, bronchitis, pneumonitis, airosacculitis, splenitis, hepatitis, nephritis and enteritis. Inflammation of the ovaries was only observed in genotype D infected chickens. Overall, the genotype D strain caused more severe histopathological lesions and a high mortality rate (54.5%) early upon infection. In addition, severity of lesions increased more rapidly in genotype D as compared to genotype B infected birds, which suggests faster replication in internal organ

The immune response against Chlamydia suis genital tract infection partially protects against re-infection

International audienceThe aim of the present study was to reveal the characteristic features of genital Chlamydia suis infection and re-infection in female pigs by studying the immune response, pathological changes, replication of chlamydial bacteria in the genital tract and excretion of viable bacteria. Pigs were intravaginally infected and re-infected with C. suis strain S45, the type strain of this species. We demonstrated that S45 is pathogenic for the female urogenital tract. Chlamydia replication occurred throughout the urogenital tract, causing inflammation and pathology. Furthermore, genital infection elicited both cellular and humoral immune responses. Compared to the primo-infection of pigs with C. suis, re-infection was characterized by less severe macroscopic lesions and less chlamydial elementary bodies and inclusions in the urogenital tract. This indicates the development of a certain level of protection following the initial infection. Protective immunity against re-infection coincided with higher Chlamydia-specific IgG and IgA antibody titers in sera and vaginal secretions, higher proliferative responses of peripheral blood mononuclear cells (PBMC), higher percentages of blood B lymphocytes, monocytes and CD8+ T cells and upregulated production of IFN-γ and IL-10 by PBMC

Prevalence of Chlamydia abortus in Belgian ruminants

Chlamydia (C.) abortus enzootic abortion still remains the most common cause of reproductive failure in sheep-breeding countries all over the world. Chlamydia abortus in cattle is predominantly associated with genital tract disease and mastitis. In this study, Belgian sheep (n=958), goats (n=48) and cattle (n=1849) were examined, using the ID Screen (TM) Chlamydia abortus indirect multi-species antibody ELISA. In the sheep, the highest prevalence rate was found in Limburg (4.05%). The animals of Antwerp, Brabant and Liege tested negative. The prevalence in the remaining five regions was low (0.24% to 2.74%). Of the nine goat herds, only one herd in Luxembourg was seropositive. In cattle, the highest prevalence rate was found in Walloon Brabant (4.23%). The animals of Limburg and Namur tested negative. The prevalence rate in the remaining seven regions ranged between 0.39% and 4.02%

Evaluation of Analgesic and Anti-Inflammatory Activities of Water Extract of Galla Chinensis In Vivo

Aim. Pain and inflammation are associated with many diseases in humans and animals. Galla Chinensis, a traditional Chinese medicine, has a variety of pharmacological properties. The purpose of this study was to evaluate analgesic and anti-inflammatory activities of Galla Chinensis through different animal models. Method. The analgesic activities were evaluated by hot-plate and writhing tests. The anti-inflammatory effects were assessed by ear edema, capillary permeability, and paw edema tests. The contents of cytokines (NO, iNOS, PGE2, and IL-10) in serum of rats in paw edema test were inspected by ELISA assays. Results. In the hot-plate test, Galla Chinensis could significantly extend pain threshold when compared to control group. The inhibitory rates of writhes ranged from 36.62% to 68.57% in Galla Chinensis-treated mice. Treatment with Galla Chinensis (1 and 0.5 g/kg) could significantly inhibit ear edema (47.45 and 36.91%, resp.; P < 0.01). Galla Chinensis (1 g/kg) had significant (P < 0.05) anti-inflammatory activity in capillary permeability test (29.04%). In carrageenan-induced edema test, the inhibitory rates were 43.71% and 44.07% (P < 0.01) at 1 h and 2 h after administration of Galla Chinensis (1 g/kg), respectively, and the levels of proinflammatory cytokines were significantly reduced. Conclusion. These results suggest that Galla Chinensis has analgesic and anti-inflammatory effects, which may be a candidate drug for the treatment of inflammation and pain

In Vivo

Aim. Dermatophytosis is one of the main fungal diseases in humans and animals all over the world. Galla chinensis, a traditional medicine, has various pharmacological effects. The goal of this study was to evaluate the treatment effect of Galla chinensis solution (GCS) on dermatophytosis-infected dogs (Microsporum canis, Microsporum gypseum, and Trichophyton mentagrophytes, resp.). Methods. The treatment effects of GCS were evaluated by mycological cure rates and clinical score comprised of three indices, including inflammation, hair loss, and lesion scale. Results. The results showed that, in the three models of dermatophytosis, GCS significantly (P<0.05) improved skin lesions and fungal eradication. GCS (10% and 5%) had higher efficacy compared to the positive control (Tujingpi Tincture). The fungal eradication efficacy exceeds 85% after treatment with GCS (10%, 5%, and 2.5%) on day 14. Conclusion. The GCS has antidermatophytosis effect in dogs, which may be a candidate drug for the treatment of dermatophytosis

Characteristics of pathology and transcriptome profiling reveal features of immune response of acutely infected and asymptomatic infected of carp edema virus in Koi

Koi sleepy disease (KSD) is a high mortality and infection viral disease caused by carp edema virus (CEV), which was a serious threat to aquaculture of common carp and export trade of Koi worldwide. Asymptomatic infection is an important cause of the difficulty in preventing KSD and its worldwide spread, because asymptomatic infection can be activated under appropriate condition. However, the understanding of the molecular correlates of these infections is still unknown. The purpose of this study was to compare the pathology change, enzyme activity, immunoglobulin activity, host and viral gene expression differences in acutely infected and cohabiting asymptomatic Koi infected with CEV. Healthy Koi were used as a control. The gross pathology, histopathology and ultrastructural pathology showed the difference and characteristics damage to the tissues of Koi under different infection conditions. Periodic Acid-Schiff stain (PAS), enzyme activity and immunoglobulin activity revealed changes in the immune response of gill tissue between acutely infected, asymptomatic infected and healthy Koi. A total of 111 and 2484 upregulated genes and 257 and 4940 downregulated genes were founded in healthy Koi vs asymptomatic infected Koi and healthy Koi vs acutely infected Koi, respectively. Additionally, 878 upregulated genes and 1089 downregulated genes were identified in asymptomatic vs. acutely infected Koi. Immune gene categories and their corresponding genes in different comparison groups were revealed. A total of 3, 59 and 28 immune-related genes were identified in the group of healthy Koi vs asymptomatic infected Koi, healthy Koi vs acutely infected Koi and asymptomatic infected Koi vs acutely infected Koi, respectively. Nineteen immune-related genes have the same expression manner both in healthy Koi vs acutely infected Koi and asymptomatic Koi vs acutely infected Koi, while 9 immune-related genes were differentially expressed only in asymptomatic Koi vs acutely infected Koi, which may play a role in viral reactivation. In addition, 8 differentially expressed genes (DEGs) were validated by quantitative reverse transcription PCR (RT-qPCR), and the results were consistent with the RNA-Seq results. In conclusion, the data obtained in this study provide new evidence for further elucidating CEV-host interactions and the CEV infection mechanism and will facilitate the implementation of integrated strategies for controlling CEV infection and spread