Therapeutic Efficacy of Phage PIZ SAE-01E2 against Abortion Caused by Salmonella enterica Serovar Abortusequi in Mice

ABSTRACT Salmonella enterica subsp. enterica serovar Abortusequi is a frequently reported pathogen causing abortion in mares. In this study, the preventive and therapeutic effects of phage PIZ SAE-01E2 against S. Abortusequi in a mouse model of abortion were investigated. Phage PIZ SAE-01E2 was stable at different temperatures (4 to 70°C) and pH values (pH 4 to 10) and could lyse the majority of the Salmonella serogroup O:4 and O:9 strains tested (25/28). There was no lysogeny-related, toxin, or antibiotic resistance-related gene in the genome of PIZ SAE-01E2. All of these characteristics indicate that PIZ SAE-01E2 has the potential for use in phage therapy. In in vivo experiments, 2 × 103 CFU/mouse of S. Abortusequi ATCC 9842 was sufficient to lead to murine abortion (gestational day 14.5) within 48 h. A single intraperitoneal inoculation of PIZ SAE-01E2 (108 PFU/mouse, multiplicity of infection = 105) 1 h before or after S. Abortusequi challenge provided effective protection to all pregnant mice (10/10). After 24 h of treatment with phage PIZ SAE-01E2, the bacterial loads in both the placenta and the uterus of the infected mice were significantly decreased (<102 CFU/g) compared to those in the placenta and the uterus of the mice in the control group (>106 CFU/g). In addition, the levels of inflammatory cytokines in the placenta and blood of the mice in the phage administration groups were significantly reduced (P < 0.05) compared to those in the placenta and blood of the mice in the control group. Altogether, these findings indicate that PIZ SAE-01E2 shows the potential to block abortions induced by S. Abortusequi in vivo. IMPORTANCE S. Abortusequi is an important pathogen that can induce abortions in mares. Although S. Abortusequi has been well controlled in Europe and the United States due to strict breeding and health policies, it is still widespread in African and Asian countries and has proven difficult to control. In China, abortions caused by S. Abortusequi have also been reported in donkeys. So far, there is no commercial vaccine. Thus, exploiting alternative efficient and safe strategies to control S. Abortusequi infection is essential. In this study, a new lytic phage, PIZ SAE-01E2, infecting S. Abortusequi was isolated, and the characteristics of PIZ SAE-01E2 indicated that it has the potential for use in phage therapy. A single intraperitoneal inoculation of PIZ SAE-01E2 before or after S. Abortusequi challenge provided effective protection to all pregnant mice. Thus, PIZ SAE-01E2 showed the potential to block abortions induced by S. Abortusequi in vivo.

COMPARATIVE STUDY OF PATHOGENICITY BETWEEN ASPERGILLUS FUMIGATUS AND PENICILLIUM CHRYSOGENUM IN MICE

This study was conducted to compare between two types of opportunistic fungi (Aspergillus fumigatus and Penicillium chrysogenum) in concerning their pathogenicity after intraperitoneal inoculation of mice. A total of twenty four male albino mice were used in this study which divided equally into 3 groups, The first and second groups were inoculated with 0.2ml of 1x 107spores/ml of A. fumigatus and P. chrysogenum intraperitonially respectively, while the third group was inoculated with normal saline which served as control group. All animals were monitored for 2 weeks after infection. The blood samples were collected by heart puncture after 18 days post infection to isolate of serum that used for biochemical analysis of liver and kidney functions. After that, all animals were sacrificed. Some internal organs of infected groups (liver, kidney, intestine, heart, spleen and lung) were taken to study the histopathological changes. It was found that there was severe histopathological changes in studied organs of infected mice particularly liver, kidney, spleen and intestine which corresponding with significant variation (p<0.01) in enzyme activities of liver and kidney like (Alanine Aminotransferase (ALT), Urea and Creatinine). Also, It was found that P. chrysogenum had more impact on these enzymes (15.65 ± 0.78, 135.23 ± 8.75 and 0.928 ± 0.02 respectively) than A. fumigatus (21.70 ± 1.04, 57.91 ± 5.99 and 0.587 ± 0.03 respectively). Therefore, the present study indicated that fungi present in the environment can induce severe inflammation reach to tissue damage in most vital internal organs So, further studies should be performed to determine the specific virulence factors and active components, which are responsible for pathogenesis of A. fumigatus and P. chrysogenum in spite of the fact that P. chrysogenum can produce antibiotic.

Complete Genome Sequence of a Colombian Zika Virus Strain Obtained from BALB/c Mouse Brain after Intraperitoneal Inoculation

A Zika virus (ZIKV) strain was isolated from an acute febrile patient during the Zika epidemics in Colombia. The strain was intraperitoneally inoculated into BALB/c mice, and 7 days postinoculation, neurological manifestations and ZIKV infection in the brain were demonstrated. The reported genome sequence is highly related to strains circulating in the Americas.

Pathomorphology of experimental Streptococcus iniae infection in tilapia (Oreochromis niloticus)

In the present study, an experimental infection with Streptococcus iniae was conducted with tilapia (Oreochromis niloticus). The bacterial agent was injected to the fish by intraperitoneal inoculation at a dose of 1 × 103 cfu / mL. Grossly, haemorrhages on tail and pectoral fins, hyperaemic and prolapsed anus, darkening and bleeding in the gills and exophthalmos in the eyes were identified in fish. Multifocal whitish foci in the liver, spleen and kidneys was observed with ascites. Histopathological changes of tissues of tilapia were studied and evaluated. Gill tissues of infected fish showed intense lymphocyte and macrophage infiltrations. In addition, epithelial cell separation and lamellar fusion with edema, lamellar curling and aneurysms were detected in gill tissue. Sinusoidal dilatation, lymphocyte infiltrations, congestion and degeneration in liver hepatocyte cells have been identified. In kidney degeneration of glomerulus and tubule cells and dense lymphocyte infiltrations were observed. Dense bacterial clusters were observed in the sinusoids of the spleen, while lymphocytes and macrophage infiltrations were found in the heart and intestinal tissues.

Nitric oxide and immune response in infection control of Caseous Lymphadenitis

ABSTRACT This study aimed to evaluate aspects of host immune response using an experimental infection model of Corynebacterium pseudotuberculosis (CP) in C57/Black6 wild-type and knockout for nitric oxide (KO-NO) mice. 28 mice were evaluated: 4 wild-type controls; 10 wild-type infected with CP; 4 KO-NO controls; 10 KO-NO infected with CP. Infection procedures were carried out by intraperitoneal inoculation using 107. Infected C57/Black6 KO-NO mice began to die after the 5° day post-inoculation, up until the 14º day. Neutrophils were found in increased numbers in the infiltrate of KO-NO murine peritoneal cavities. Examination of splenic tissue revealed an accumulation of lymphocytes, predominantly CD8 T-cells, in experimental animal groups. KO-NO animals were found to have a predominance of granulomas 7 days post-inoculation, primarily in the lymph nodes. In addition, greater amounts of bacteria were recovered from the mesenteric lymph nodes of KO-NO mice. There was no statistically significant difference in the levels of total IgG and its subclasses 14 days post-inoculation between KO-NO and wild groups. The results suggest the importance of nitric oxide in the process of controlling CP infection, as KO-NO animals were observed to be markedly more affected by infection with this bacterium.

Heparinase Is Essential for Pseudomonas aeruginosa Virulence during Thermal Injury and Infection

ABSTRACTThe opportunistic pathogenPseudomonas aeruginosais a major cause of sepsis in severely burned patients. If it is not eradicated from the wound, it translocates to the bloodstream, causing sepsis, multiorgan failure, and death. We recently described theP. aeruginosaheparinase-encoding gene,hepP, whose expression was significantly enhanced whenP. aeruginosastrain UCBPP_PA14 (PA14) was grown in whole blood from severely burned patients. Further analysis demonstrated thathepPcontributed to thein vivovirulence of PA14 in theCaenorhabditis elegansmodel. In this study, we utilized the murine model of thermal injury to examine the contribution ofhepPto the pathogenesis ofP. aeruginosaduring burn wound infection. Mutation ofhepPreduced the rate of mortality from 100% for mice infected with PA14 to 7% for mice infected with PA14::hepP. While comparable numbers of PA14 and PA14::hepPbacteria were recovered from infected skin, only PA14 was recovered from the livers and spleens of infected mice. Despite its inability to spread systemically, PA14::hepPformed perivascular cuffs around the blood vessels within the skin of the thermally injured/infected mice. Intraperitoneal inoculation of the thermally injured mice, bypassing the need for translocation, produced similar results. The rate of mortality for mice infected with PA14::hepPwas 0%, whereas it was 66% for mice infected with PA14. As before, only PA14 was recovered from the livers and spleens of infected mice. These results suggest thathepPplays a crucial role in the pathogenesis of PA14 during burn wound infection, most likely by contributing to PA14 survival in the bloodstream of the thermally injured mouse during sepsis.

Antitumor activity and antioxidant status of Streblus asper bark against Dalton's ascitic lymphoma in mice

Streblus asper Lour (Moraceae), commonly known as Siamee Rough Brush in English is widely distributed in subtropical Asia and traditionally used for several medicinal purposes. In the present study, the ethyl acetate fraction of the methanol extract from Streblus asper bark (EASA) was evaluated for antitumor effect against Dalton’s ascitic lymphoma (DAL) in Swiss albino mice. Twenty-four hours after intraperitoneal inoculation of DAL cells in mice, EASA was administered intraperitoneally at 200 and 400 mg/kg body weight for 9 consecutive days. On the 10th day, half of the mice were sacrificed to determine the tumor growth parameters, and the rest were kept alive for survival assessment. Hematological, serum biochemical and tissue (liver, kidney) antioxidant profiles were also determined. EASA exhibited significant and dose dependent decrease in tumor growth parameters and increased survival of DAL bearing animals. EASA significantly and dose-dependently normalized the altered hematological, serum biochemical and tissue antioxidant parameters as compared with the DAL control mice. From the present study it may be concluded that S. asper bark possesses remarkable antitumor efficacy mediated by amelioration of oxidative stress by multiple mechanisms.

Study of histopathological changes in brian of mice infected with Toxoplasma gondii isolated from domestic rabbit

The study was designed to determine the infection rate of Toxoplasma gondii in the rabbits and histopathological changes of infected internal organs in mice. A total of 60 blood samples were collected from clinically healthy rabbits from different region of Baghdad city for the serological detection of T. gondii infection. Biological assay in mice was performed by intraperitoneal inoculation of 0.1 ml digested organs suspension, (lungs, heart, liver, spleen, kidney, muscles, and brain) during the period from October 2013 until July 2014. The results revealed histopathological changes in bioassay mice infected by T. gondii isolated from domestic rabbit, no histopathological changes in the brain of animals of first group1 (control group), but in the group 2 (killed at day 15) the main pathological changes were perivascular perineuronal edema with presence of some degenerated neurons characterized by shrunken dark blue stained (basophilic) cell bodies. In the animals of the group 2 (killed at day 21) the main brain histopathological changes were Sever congestion of meningeal blood vessels with infiltration of inflammatory cells and focal aggregation of microglial cells with diffuse obvious focal gliosis, whereas, in the same group animals that killed at day 28 the main brain histopathological changes were focal encephalomalacia and edema between molecular and granular layer.