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Background There is an urgent need to develop and test novel compounds against malaria infection. Carrageenans, sulphated polysaccharides derived from seaweeds, have been previously shown to inhibit Plasmodium falciparum in vitro. However, they are inflammatory and alter the permeability of the blood-brain barrier, raising concerns that their use as a treatment for malaria could lead to cerebral malaria (CM), a severe complication of the disease. In this work, the authors look into the effects of the administration of λ-carrageenan to the development and severity of CM in BALB/c mice, a relatively non-susceptible model, during infection with the ANKA strain of Plasmodium berghei. Methods Five-week-old female BALB/c mice were infected with P. berghei intraperitoneally. One group was treated with λ-carrageenan (PbCGN) following the 4-day suppressive test protocol, whereas the other group was not treated (PbN). Another group of healthy BALB/c mice was similarly given λ-carrageenan (CGN) for comparison. The following parameters were assessed: parasitaemia, clinical signs of CM, and mortality. Brain and other vital organs were collected and examined for gross and histopathological lesions. Evans blue dye assays were employed to assess blood-brain barrier integrity. Results Plasmodium berghei ANKA-infected BALB/c mice treated with ?-carrageenan died earlier than those that received no treatment. Histopathological examination revealed that intracerebral haemorrhages related to CM were present in both groups of infected BALB/c mice, but were more numerous in those treated with λ-carrageenan than in mock-treated animals. Inflammatory lesions were also observed only in the λ-carrageenan-treated mice. These observations are consistent with the clinical signs associated with CM, such as head tilt, convulsions, and coma, which were observed only in this group, and may account for the earlier death of the mice. Conclusion The results of this study indicate that the administration of λ-carrageenan exacerbates the severe brain lesions and clinical signs associated with CM in BALB/c mice infected with P. berghei ANKA. [ABSTRACT FROM AUTHOR]

This study aimed to examine expression and microstructural distribution of prestin in outer hair cells, and the effect of dose and time of radiation on prestin expression in the BALB/c mouse. We also investigated the molecular biological characteristics of prestin and possible mechanisms of sensorineural hearing loss caused by radiation. Seventy 4-week-old mice were randomly divided into four groups, including one control group and three experimental groups. Each experimental group was randomly divided into two groups, which were killed to collect specimens of the cochlea on the 3rd and 7th days after exposure to different doses of 8, 12, and 16 Gy radiation. These cochleas were embedded in paraffin, and then cut into sections. The sections were immunostained with anti-prestin antibodies. The distribution of prestin was observed under optical microscopy and the density of prestin-positive expression was quantitatively calculated by Image-Pro Plus. Prestin had high expression in the lateral membrane and low expression in the cytoplasm of outer hair cells above the nucleus. The density of prestin protein expression of the basal turn was not significantly different after exposure to the different doses of radiation compared with the control group, but up-regulation occurred after radiation in the apex turn. We conclude that prestin protein is mainly expressed in the lateral membrane above the nucleus. Prestin protein may be responsible for the mechanism of injury to the inner ear caused by radiation. [ABSTRACT FROM AUTHOR]

Viral vectors are a potent vaccine platform for inducing humoral and T-cell immune responses. Among the various viral vectors, replication-competent ones are less commonly used for coronavirus disease 2019 (COVID-19) vaccine development compared with replication-deficient ones. Here, we show the availability of a smallpox vaccine LC16m8Δ (m8Δ) as a replication-competent viral vector for a COVID-19 vaccine. M8Δ is a genetically stable variant of the licensed and highly effective Japanese smallpox vaccine LC16m8. Here, we generated two m8Δ recombinants: one harbouring a gene cassette encoding the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike (S) glycoprotein, named m8Δ-SARS2(P7.5-S)-HA; and one encoding the S protein with a highly polybasic motif at the S1/S2 cleavage site, named m8Δ-SARS2(P7.5-S HN )-HA. M8Δ-SARS2(P7.5-S)-HA induced S-specific antibodies in mice that persisted for at least six weeks after a homologous boost immunization. All eight analysed serum samples displayed neutralizing activity against an S-pseudotyped virus at a level similar to that of serum samples from patients with COVID-19, and more than half (5/8) also had neutralizing activity against the Delta/B.1.617.2 variant of concern. Importantly, most serum samples also neutralized the infectious SARS-CoV-2 Wuhan and Delta/B.1.617.2 strains. In contrast, immunization with m8Δ-SARS2(P7.5-S HN )-HA elicited significantly lower antibody titres, and the induced antibodies had less neutralizing activity. Regarding T-cell immunity, both m8Δ recombinants elicited S-specific multifunctional CD8 + and CD4 + T-cell responses even after just a primary immunization. Thus, m8Δ provides an alternative method for developing a novel COVID-19 vaccine.

Thorium (232Th), long lived (14.05 billion years) most stable thorium isotope, is thrice naturally abundant than uranium. 232Th occurs as rocky deposits and black monazite sands on the earth's crust geographically distributed in coastal South India and other places globally. Monazite sand comprises of cerium and large quantities of radioactive thorium. The environmental hazard lies in monazite rich area being termed as High Background Radiation Area (HBRA). In this study, we mimicked the HBRA under controlled chamber conditions using thorium oxalate as a thorium source for BALB/c mice exposure. Furthermore, sequential radio-disintegration of 232 Th leads to thoron (220Rn), the noble gas and other daughter products/progeny predominantly via alpha decay/emissions. Such progeny tend to attach to aerosol and dust particles having potential inhalation hazard followed by alpha emissions and damages that we evaluated in mouse lung tissues post thoron inhalation. Secondly, along with the radio disintegration and alpha emission, high energy gamma is also generated that can travel to various distant organs through the systemic circulation, as significant findings of our study as damages to the liver and kidney. The mechanistic findings include the damages to the hematological, immunological and cellular antioxidant systems along with activation of canonical NF-κβ pathway via double stranded DNA damage. [Display omitted] • Thorium toxicity ascertained via inhaled thorium progeny deposition & organ damage. • Inhaled thorium progeny induced systemic, as well as, lung inflammation. • Highest progeny mean equivalent dose deposition was observed in lungs. • Progeny toxicity altered haematological, immunological & antioxidant machinery. • Oxidative stress induced double stranded DNA damage following activation of NF-κβ pathway. [ABSTRACT FROM AUTHOR]

Highlights: [•] We compare partial genes of Angiostrongylus cantonensis from five regions in Taiwan. [•] Two distinct strains are discovered and Hualien strain is never reported before. [•] We compare the infectivity and pathogenicity of Pingtung strain and Hualien strain in hosts. [•] Hualien strain leads to lower infectivity and causes milder pathology in hosts. [ABSTRACT FROM AUTHOR]

Due to their unique properties, bone marrow-derived Lin cells can be used to regenerate damaged tissues, including skin. The objective of our study was to determine the influence of the skin tissue-specific microenvironment on mouse Lin cell proliferation and migration in vitro. Cells were analyzed for the expression of stem/progenitor surface markers by flow cytometry. Proliferation of MACS-purified cells in 3D cultures was investigated by WST-8 assay. Lin cell migration was evaluated by in vitro scratch assay. The results obtained show that basement membrane matrix is more effective for Lin cell proliferation in vitro. However, type I collagen matrix better enhances the re-epithelization process, that depends on the cell migratory properties. These studies are important for preparing cells to be used in transplantation. [ABSTRACT FROM AUTHOR]

مقدمه: استفاده از واكسن‌های مبتنی بر پروتئین‌های شوك حرارتی (Heat shock proteins یا HSPs)، عرصه‌ی جدیدی از تحقیقات علوم پزشكی را رقم زده است و امیدهای جدیدی را برای پیش‌گیری و درمان بیماری‌های عفونی و تومورهای سرطانی به وجود آورده است. در این تحقیق به منظور تهیه‌ی لیزات غنی از HSPs از سلول‌های طحالی موش‌های ایمن شده با كاندیدا، ارزیابی اثر شوك ناشی از تزریق كاندیدا آلبیكنس زنده بر تركیب جمعیتی و الگوی پروتئینی لیزات سلول‌های طحالی با تأكید بر تغییرات HSPs مد نظر قرار گرفت. روش‌ها: تعداد 30 سر موش BALB/c پس از عادت دادن به محیط نگهداری، به دو گروه مداخله و شاهد تقسیم شدند. در گروه مداخله، پس از چندین مرحله‌ تزریق تقویت‌كننده‌ی کاندیدا، دوز نهایی به‌ صورت 106 × 4 عدد كاندیدا آلبیكنس زنده در هر موش از طریق ورید دمی تزریق شد. 7 روز بعد از تزریق نهایی، موش‌های مداخله و شاهد از طریق قطع نخاع كشته شدند و سلول‌های طحالی آن‌ها به صورت خالص تهیه گردید. میزان كل سلول‌های طحال و درصد افتراقی آن‌ها تعیین شد و سپس لیزات تهیه شده از تعداد معینی سلول طحالی برای تعیین میزان HSP70 با روش ELISA و الگوی پروتئینی با روش الكتروفورز SDS-PAGE مورد سنجش قرار گرفت. یافته‌ها: تزریق كاندیدا منجر به افزایش تعداد مطلق سلول‌های طحال شد. از نظر شمارش افتراقی نیز درصد ماكروفاژ‌ها افزایش معنی‌داری پیدا کرد. مقایسه‌ی میزان HSP70 سلول‌های طحالی در گروه مداخله، افزایش 13 برابری این پروتئین‌ها را نسبت به گروه شاهد نشان داد (001/0 > P). همچنین، مقایسه‌ی الگوی الكتروفورتیكی دو گروه (SDS-PAGE+Western) افزایش 11 و 3/7 برابری را به ترتیب در میزان HSP70 و HSP90 در گروه مداخله نسبت به شاهد نشان داد. نتیجه‌گیری: تزریق وریدی كاندیدا آلبیكنس ضمن افزایش جمعیت منوسیت و ماكروفاژها در طحال، میزان HSPs را به ازای هر سلول نیز افزایش چشمگیری می‌دهد، كه بیشترین افزایش مربوط به HSP70 و HSP90 می‌باشد.

Highlights: [•] The Balb/c mouse is a model of autism spectrum disorders. [•] d-Cycloserine improves the sociability of Balb/c mice. [•] d-Cycloserine increased social salience of Balb/c mice for the C57Bl/6 strain. [•] Data suggest that d-cycloserine may normalize social cues emitted by the Balb/c mouse. [ABSTRACT FROM AUTHOR]

Background: The current study was conducted to establish animal models (including mouse and ferret) for the novel avian-origin H7N9 influenza virus. Findings: A/Anhui/1/2013 (H7N9) virus was administered by intranasal instillation to groups of mice and ferrets, and animals developed typical clinical signs including body weight loss (mice and ferrets), ruffled fur (mice), sneezing (ferrets), and death (mice). Peak virus shedding from respiratory tract was observed on 2 days post inoculation (d.p.i.) for mice and 3-5 d.p.i. for ferrets. Virus could also be detected in brain, liver, spleen, kidney, and intestine from inoculated mice, and in heart, liver, and olfactory bulb from inoculated ferrets. The inoculation of H7N9 could elicit seroconversion titers up to 1280 in ferrets and 160 in mice. Leukopenia, significantly reduced lymphocytes but increased neutrophils were also observed in mouse and ferret models. Conclusions: The mouse and ferret model enables detailed studies of the pathogenesis of this illness and lay the foundation for drug or vaccine evaluation. [ABSTRACT FROM AUTHOR]

Background: Dietary supplementation with unique prebiotic nondigestible carbohydrates has been shown to suppress allergy. In the present study, the prophylactic efficacy of a disaccharide β, 4 mannobiose (MNB) in a BALB/C mouse model of intranasally-induced pollen allergy was characterized. Methods: Balb/c mice were pretreated with MNB orally and sensitized with pollen extract intraperitoneally and intranasally and challenged with histamine and crude pollen extract. Outcomes were measured as clinical signs, antibody isotypes, cytokine gene and protein expression patterns. Results: The MNB-treated mice had lower sneezing frequency as compared to the positive control mice (P < 0.05). The low dose MNB-treated mice had less histamine (P < 0.05). However, the Cry j1 and Cry j 2-specific IgE, IgG, lgG1 and lgG2a antibody activity did not differ between groups (P > 0.05). The MNB-treated mice had increased IFN-γ (P < 0.05), and decreased IL-4 (P < 0.05). Mice in the high dose group had increased IL-10 (P < 0.05). However, TGF-β and IL-17 concentration did not differ between groups (P > 0.05). Both total and Cry j1 and Cry j 2-specific IgA were increased in the high dose group. Real-time RT-PCR analysis indicated that IL-4 and IL-17 mRNA expression were lower in MNB-treated mice (P < 0.05). Conclusions: This work provides insights into using MNB as a potential prebiotic immunomodulator via decreased clinical signs, improved type1/type 2 balance, and IgA production, thus validating the potential use of MNB as a prophylactic prebiotic candidate to attenuate allergic response. [ABSTRACT FROM AUTHOR]

Background: Nutritional prebiotic supplementation represents an attractive approach for interventions of allergy. In this study, the potential therapeutic effect of β, 4 mannobiose (MNB) in a murine model of cedar pollinosis was investigated. Methods: Groups of Balb/c mice were intranasally sensitized to Japanese cedar pollen extract, and subsequently administered with low or high dose MNB. Both intraperitoneal and intranasal challenges were performed to monitor for clinical signs. Frequency of sneezing was recorded. Serum, spleen and Peyer's patches were collected for various biomarker analyses. Anti-allergic activity of MNB using RBL-2H3 cells was also evaluated. Results: Significant decrease in sneezing frequency, histamine, interleukin (IL)-4 and IL-17A and increase in TGF-β and IL-10 concentration were exhibited by the MNB-treated mice. However, Cry j1 and Cry j 2-specific IgE activity remained unaltered. The high dose MNB treatment increased total IgA activity and IL-10, TGF-β and FoxP3 and decreased IL-4, IL-17A, and RORγT mRNA expression. Inhibition of activation of RBL-2H3 cells was observed via decrease in histamine, intracellular Ca2+ concentration, and FcεRI mRNA expression. Conclusions: We demonstrated the immunomodulatory effects of MNB and conclude that MNB is a potential therapeutic molecular nutritional supplement candidate for treatment of pollen allergy. [ABSTRACT FROM AUTHOR]

Moloney murine leukemia virus (MLV) infects BALB/c mice and induces T-cell lymphoma in mice. Retroviral integration is mediated by the interaction of the MLV integrase (IN) with members of the bromodomain and extraterminal motif (BET) protein family (BRD2, BRD3, and BRD4). The introduction of the W390A mutation into MLV IN abolishes the BET interaction. Here, we compared the replication of W390A MLV to that of wild-type (WT) MLV in adult BALB/c mice to study the role of BET proteins in replication, integration, and tumorigenesis in vivo . Comparing WT and W390A MLV infections revealed similar viral loads in the blood, thymus, and spleen cells. Interestingly, W390A MLV integration was retargeted away from GC-enriched genomic regions. However, both WT MLV- and W390A MLV-infected mice developed T-cell lymphoma after similar latencies represented by an enlarged thymus and spleen and multiorgan tumor infiltration. Integration site sequencing from splenic tumor cells revealed clonal expansion in all WT MLV- and W390A MLV-infected mice. However, the integration profiles of W390A MLV and WT MLV differed significantly. Integrations were enriched in enhancers and promoters, but compared to the WT, W390A MLV integrated less frequently into enhancers and more frequently into oncogene bodies such as Notch1 and Ppp1r16b . We conclude that host factors direct MLV in vivo integration site selection. Although BET proteins target WT MLV integration preferentially toward enhancers and promoters, insertional lymphomagenesis can occur independently from BET, likely due to the intrinsically strong enhancer/promoter of the MLV long terminal repeat (LTR). IMPORTANCE In this study, we have shown that the in vivo replication of murine leukemia virus happens independently of BET proteins, which are key host determinants involved in retroviral integration site selection. This finding opens a new research line in the discovery of alternative viral or host factors that may complement the dominant host factor. In addition, our results show that BET-independent murine leukemia virus uncouples insertional mutagenesis from gene enhancers, although lymphomagenesis still occurs despite the lack of an interaction with BET proteins. Our findings also have implications for the engineering of BET-independent MLV-based vectors for gene therapy, which may not be a safe alternative.

The yeast cell wall (YCW) is composed mainly of β-glucans, mannoproteins, and chitin. β-Glucans are well known immunomodulators, recognized by Toll-like receptor-4 (TLR-4) and inducing the nuclear factor-kappaB (NF-κB) signaling pathway, which is implicated in the synthesis of pro-inflammatory mediators such as interleukin-1beta (IL-1β), tumor necrosis factor-alpha (TNF-α), and nitric oxide (NO). Here we evaluated the immunomodulating effect of the YCW extracts from three different strains of Saccharomyces cerevisiae (AR5, MG, and L013) obtained from Tequila and bread-making processes by challenging intraperitoneal macrophages from BALB/c mice with YCW extract and/or lipopolysaccharide (LPS) endotoxin from Escherichia coli. Only the extract from AR5, which had a high glucan-to-mannan ratio, exhibited an antagonistic effect upon LPS stimulation: The IL-1β and TNF-α concentrations in plasma increased slightly by 24% and 4%, respectively, and the NO level increased moderately by 200% compared with the control. When the YCW extracts had less glucan, as found for MG and L013, the LPS stimulus had more of a synergistic effect on the plasma IL-1β concentration, which increased about 175%, and on the NO level, which rose 330–470%. These results indicated that under certain conditions, YCW extracts have an immune-attenuating effect; that is, the mice liberated much less IL-1β or nearly equal amounts of TNF-α or NO compared with the LPS stimulus alone. [ABSTRACT FROM AUTHOR]

Background and Aim: Leishmanization (LZ) is an effective tool to prevent cutaneous leishmaniasis. Standardization of Leishmania is the main drawback of LZ. The aim of this study was to assess the effect of various preservatives on the infectivity of Leishmania. Methods: L .major harvested at different stages of growth; logarithmic, early and late stationary phases were frozen using various preservatives of saccharose, glycerol, trehalose, glucose, sorbitol, and dimethyl sulfoxide (DMSO). The harvested parasites were inoculated into BALB/c mice before and after freezing. The infectivity of the parasites was checked. IFA test was used to assess the rate of metacyclic parasite. Results: The ratio of live Leishmania in different growth stages and various preservatives were 89.0% to 98.2%. The lesion development in groups of mice which received Leishmania in sacarose + glycerol or DMSO was started from 3rd week and at 5th week all the mice showed lesion. The group of mice which were inoculated with early or late stationary phases in saccharose + glucose, saccharose + glycerol, glycerol 15% or DMSO showed lesion from 4th to 5th week and in 100% showed lesions at 8th week. The rate of metacyclic parasites increases from log phase to early and late stationary phases. Conclusion: There was a correlation between percent of live parasite and the rate of lesion development in BALB/c mice. Saccharose 22.5% + Glyserol 22.5% were the most appropriate preservative to freeze L. major. IFA test is used to detect metacyclic Leishmania. A correlation was seen between the rate of lesion development in BALB/c mice and IFA positivity. [ABSTRACT FROM AUTHOR]

Abstract: Anti-tumour activity and membrane permeability of 1kDa oligogalacturonide (PET-pectin), prepared from citrus pectin after 24h hydrolysis, by commercial pectic enzyme produced by Aspergillus niger, on four human cell lines (HepG2, A549, Colo 205, and HEK293) and the uptake of oligogalacturonide by HEK293 cell and BALB/c mouse were investigated. PET-pectin causes a higher value of growth inhibition, lactate dehydrogenase release, and galactin-3 release in human cancer cells, as compared to the human normal HEK293 cell. There was a good correlation between growth inhibition of human cells and the uptake of rhodamine B-PET-pectin content by these cells. Additionally, almost no difference between growth inhibitions of human normal HEK293 cells cultivated with PET-pectin and pectin was found. Total pectin content in the blood of PET-pectin administrated mice increased to a maximum at 2h after oral administration, while it did not increase and change in pectin administrated mice. Our findings suggested that citrus PET-pectin can be developed as a potential dietary supplement in plant origin for cancer prevention. [Copyright &y& Elsevier]

Background: Knowledge of allergen-specific T cell epitopes is a prerequisite not only for therapeutic approaches but also for elucidating immunological mechanisms of type I allergy. Ex vivo detection of allergen-specific T cells using class II tetramer technology has become an important tool for investigating immune responses in atopic and healthy individuals. Methods: Using 3H-thymidine incorporation assays, T cell epitopes specific for the major timothy grass pollen allergen Phl p 5.0101 were mapped in 11 allergic donors and two different mouse strains. Different protocols for expansion/restimulation of T cells from the blood of allergic donors and detection of allergen-specific T cells by Class II Ultimer staining were evaluated. Results: We identified several new Phl p 5.0101 class II T cell epitopes in allergic patients and confirmed previously published ones. Additionally, we discovered the major T cell epitopes in BALB/c and C57BL/6 mice. Using a novel Class II Ultimer, we detected epitope-specific T cells expanded from the blood of an allergic donor. Conclusions: Epitope mapping of Phl p 5.0101 revealed an immunodominant epitope in BALB/c and C57BL/6 mice and an immunodominant region in humans (amino acids 259-282), which was recognized by 8 out of 11 allergic donors. Detection of Phl p 5-specific T cells was demonstrated using a Class II Ultimer specific for epitope 196-210. Successful detection of ultimer-positive T cells was strongly dependent on a resting phase after in vitro expansion. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Regarding the immunomodulatory effects of lactobacillus bacteria, this study aimed to evaluate the effect of oral administration of Lactobacillus reuteri, as probiotic bacteria, on natural killer cell cytotoxicity and tumor-specific lymphocyte proliferation in Balb/c mice with breast adenocarcinoma. Methods: A total of 30 female mice, aged 6- 8 weeks and with a weight of approximately 17- 19 g, were randomly divided into two groups of 15 mice. The case group received Lactobacillus reuteri at a dose of 2.7× 108 bacteria in half a milliliter of sterile phosphate buffer saline (PBS) and the control group only received PBS. The probiotic group received the regimen for two weeks prior to tumor transplantation, as they did for 30 days after transplantation with three-day intervals and durations of seven days. For the evaluation of natural killer cell cytotoxicity and also tumor-specific lymphocyte proliferation response, LDH and BrdU assays were performed respectively according to the manufacturers' instructions. Results: The study showed that the mice in the case group which were receiving Lactobacillus reuteri had statistically significant differences in the replication of tumor -specific lymphocytes, natural killer cell cytotoxicity and delayed hypersensitivity responses Compared to the mice in the control group. Conclusion: Daily consumption of probiotics seems to regulate the immune system and consequently it can be helpful in people with cancer. Moreover, consumption of probiotics in healthy individuals can also boost the efficiency of the immune system against a variety of abnormalities. [ABSTRACT FROM AUTHOR]

Background: Developing a new generation of vaccines based on heat shock protein (HSP) is a new emerging field of medical researches that makes new promises to effective prevention or eradication of infectious diseases and cancers. The current study was designed to evaluate the effects of systemic injection of live Candida albicans on counts and compositions of splenocytes. It also surveyed the electrophoretic profile of the cells lysates with special focus on HSP molecules. Methods: A total number of 30 inbreed BALB/c mice were purchased. After adaptation to the animal house, they were divided into 2 groups (a test and a control group). Following booster immunizations using the multistep injection protocol, the mice in the test group received a high dose of 4x106 cells of live Candida albicans through the tail vein. All of the mice were killed on day 7, and the splenocytes suspensions were prepared aseptically. Total and differential counting of cells were performed using hematologic staining and microscopic observation. HSP90 contents of the splenocytes were assayed using a standard enzyme-linked immunosorbent assay (ELISA) kit. The cell lysates went under electrophoretic and western blot analysis using HSP70 and HSP90 specific antibodies. Findings: Systemic Candida injection to mice led to increased total spleen cells and significant increment of monocyte differential counts. The splenocytes from the test group showed 13 folds increase in HSP70 contents (ELISA, P < 0.001). Electrophoretic analysis followed by western blotting of the cells lysates showed 11 and 7.3 folds increments in HSP70 and HSP90 contents, respectively, compared to the controls. Conclusion: Systemic injection of live Candida albicans leads to accumulation of the macrophages in the spleen. It also significantly increases the mean HSP70 and HSP90 contents of each splenocyte. [ABSTRACT FROM AUTHOR]

Abstract: Various fluorodeoxyribonucleosides were evaluated for their antiviral activities against influenza virus infections in vitro and in vivo. Among the most potent inhibitors was 2′-deoxy-2′-fluorocytidine (2′-FdC). It inhibited various strains of low and highly pathogenic avian influenza H5N1 viruses, pandemic H1N1 viruses, an oseltamivir-resistant pandemic H1N1 virus, and seasonal influenza viruses (H3N2, H1N1, influenza B) in MDCK cells, with the 90% inhibitory concentrations ranging from 0.13 to 4.6μM, as determined by a virus yield reduction assay. 2′-FdC was then tested for efficacy in BALB/c mice infected with a lethal dose of highly pathogenic influenza A/Vietnam/1203/2004 H5N1 virus. 2′FdC (60mg/kg/d) administered intraperitoneally (i.p.) twice a day beginning 24h after virus exposure significantly promoted survival (80% survival) of infected mice (p =0.0001). Equally efficacious were the treatment regimens in which mice were treated with 2′-FdC at 30 or 60mg/kg/day (bid X 8) beginning 24h before virus exposure. At these doses, 70–80% of the mice were protected from death due to virus infection (p =0.0005, p =0.0001; respectively). The lungs harvested from treated mice at day four of the infection displayed little surface pathology or histopathology, lung weights were lower, and the 60mg/kg dose reduced lung virus titers, although not significantly compared to the placebo controls. All doses were well tolerated in uninfected mice. 2′-FdC could also be administered as late as 72h post virus exposure and still significantly protect 60% mice from the lethal effects of the H5N1 virus infection (p =0.019). Other fluorodeoxyribonucleosides tested in the H5N1 mouse model, 2′-deoxy-5-fluorocytidine and 2′-deoxy-2′,2′-difluorocytidine, were very toxic at higher doses and not inhibitory at lower doses. Finally, 2′-FdC, which was active in the H5N1 mouse model, was also active in a pandemic H1N1 influenza A infection model in mice. When given at 30mg/kg/d (bid X 5) beginning 24h before virus exposure), 2′-FdC also significantly enhanced survival of H1N1-infected mice (50%, p =0.038) similar to the results obtained in the H5N1 infection model using a similar dosing regimen (50%, p <0.05). Given the demonstrated in vitro and in vivo inhibition of avian influenza virus replication, 2′FdC may qualify as a lead compound for the development of agents treating influenza virus infections. [Copyright &y& Elsevier]

Summary The effects of a sesquiterpene lactone, dehydroleucodine, on the reproductive tract were investigated using adult male mice. Dehydroleucodine was dissolved in tap water and administered as drinking water for 30 days. All the parameters were compared with a control group that received only vehicle. Animals were killed by decapitation and the trunk blood, the testes and the epididymes were collected. Plasma concentrations of testosterone and oestradiol, and testicular weight and concentration of spermatids did not change by dehydroleucodine. Nevertheless, in epididymal cauda dehydroleucodine treatment caused a diminution in sperm number, a decrease in the amount of tubular fluid and a reduction in the activity of the hydrolytic enzyme N-acetyl-β- d-glucosaminidase. However, the sperm motility was not altered by dehydroleucodine treatment, although sperm binding to zona-free oocytes increased significantly. These results suggest that dehydroleucodine, which has been implicated in the inhibition of aromatase P450, does not affect the plasma concentration of testosterone and oestradiol or testicular activity, whereas altering several epididymal parameters. The epididymis is thus a more sensitive target for dehydroleucodine action. [ABSTRACT FROM AUTHOR]

Abstract: The ability of MK-801 (dizocilpine), a noncompetitive N-methyl D-aspartate (NMDA) antagonist, to antagonize electrical seizures is reduced in stressed mice. Stress-associated alterations in seizure susceptibility and diminished efficacy of antiseizure medications in humans have been reported [Joëls, 2009; Haut et al., 2007; Moshe et al., 2008]; thus, these experimental observations implicate altered endogenous tone of NMDA receptor-mediated neurotransmission in clinically adverse effects of stress on seizure proneness and treatment. The current exploratory experiment examined the effect of 2-methyl-6-(phenylethynyl)-pyridine (MPEP), an antagonist of mGluR5, administered prior to stress on the stress-induced reduction of MK-801''s antiseizure effect in Swiss–Webster and Balb/c mice; the Balb/c mouse is behaviorally hypersensitive to MK-801. Interestingly, the data suggest that MPEP can attenuate the severity of the stress-induced reduction of MK-801''s antiseizure effect in the Balb/c strain. Thus, mGluR5 could serve as a target for strategies for adjuvant treatment of seizures exacerbated by stress. [Copyright &y& Elsevier]

Abstract: Urtica dioica agglutinin (UDA) is a small plant monomeric lectin, 8.7kDa in size, with an N-acetylglucosamine specificity that inhibits viruses from Nidovirales in vitro. In the current study, we first examined the efficacy of UDA on the replication of different SARS-CoV strains in Vero 76 cells. UDA inhibited virus replication in a dose-dependent manner and reduced virus yields of the Urbani strain by 90% at 1.1±0.4μg/ml in Vero 76 cells. Then, UDA was tested for efficacy in a lethal SARS-CoV-infected BALB/c mouse model. BALB/c mice were infected with two LD50 (575PFU) of virus for 4h before the mice were treated intraperitoneally with UDA at 20, 10, 5 or 0mg/kg/day for 4 days. Treatment with UDA at 5mg/kg significantly protected the mice against a lethal infection with mouse-adapted SARS-CoV (p <0.001), but did not significantly reduce virus lung titers. All virus-infected mice receiving UDA treatments were also significantly protected against weight loss (p <0.001). UDA also effectively reduced lung pathology scores. At day 6 after virus exposure, all groups of mice receiving UDA had much lower lung weights than did the placebo-treated mice. Thus, our data suggest that UDA treatment of SARS infection in mice leads to a substantial therapeutic effect that protects mice against death and weight loss. Furthermore, the mode of action of UDA in vitro was further investigated using live SARS-CoV Urbani strain virus and retroviral particles pseudotyped with SARS-CoV spike (S). UDA specifically inhibited the replication of live SARS-CoV or SARS-CoV pseudotyped virus when added just before, but not after, adsorption. These data suggested that UDA likely inhibits SARS-CoV infection by targeting early stages of the replication cycle, namely, adsorption or penetration. In addition, we demonstrated that UDA neutralizes the virus infectivity, presumably by binding to the SARS-CoV spike (S) glycoprotein. Finally, the target molecule for the inhibition of virus replication was partially characterized. When UDA was exposed to N-acetylglucosamine and then UDA was added to cells just prior to adsorption, UDA did not inhibit the virus infection. These data support the conclusion that UDA might bind to N-acetylglucosamine-like residues present on the glycosylated envelope glycoproteins, thereby preventing virus attachment to cells. [Copyright &y& Elsevier]

Abstract: The Balb/c mouse strain shows quantitative deficits of sociability and is behaviorally-hypersensitive to MK-801 (dizocilpine), a noncompetitive NMDA receptor antagonist. D-Serine (560mg/kg, intraperitoneally), a full agonist for the obligatory glycine co-agonist binding site on the NMDA receptor, increased the amount of time Balb/c mice spend in a compartment containing the enclosed social stimulus mouse and the amount of time Balb/c mice spend exploring (sniffing) an inverted cup containing the enclosed social stimulus mouse in a standard sociability apparatus. These effects of D-serine on the impaired sociability of the Balb/c mouse strain were not due to a “nonspecific” effect on locomotor activity; importantly, the locomotor activity of the Balb/c mouse strain decreases in the presence of an enclosed or freely-moving social stimulus mouse. The data suggest that dimensions of the impaired sociability of the Balb/c mouse strain may be improved by targeted NMDA receptor agonist interventions. [ABSTRACT FROM AUTHOR]

Abstract: The genetically inbred Balb/c mouse strain shows evidence of impaired sociability in a standard paradigm. For example, relative to 8-week-old male outbred Swiss-Webster mice, 8 week-old male Balb/c mice spend less time sniffing and in the vicinity of an enclosed 4 week-old male ICR stimulus mouse and, when allowed to interact freely with the stimulus mouse for five minutes, make fewer discrete episodes of social approach and show suppression of locomotor activity. We explored the effect of d-cycloserine (320mg/kg, intraperitoneally), a partial glycine agonist that binds to the obligatory co-agonist glycine binding site on the NMDA receptor, on the sociability of the Balb/c and Swiss-Webster mouse strains in a standard paradigm. The results show that treatment with d-cycloserine increased the locomotor activity of the Balb/c mouse strain in the presence of an enclosed social stimulus mouse and when these mice were allowed to interact freely with each other. Also, d-cycloserine increased the number of discrete episodes of social approach when Balb/c mice were allowed to interact freely with social stimulus mice. However, d-cycloserine had similar effects on measures of sociability in the Swiss-Webster mouse, raising the possibility that the positive effects on the sociability of the Balb/c mouse strain may be mediated by indirect effects on locomotion, arousal, and anxiety. [ABSTRACT FROM AUTHOR]

Background Peptide-based immunotherapy (PIT) represents an attractive approach for targeted interventions in immunological disorders, but has not been widely explored in the context of food allergy. Objective In this study, we built on the information obtained from the recent identification of three immunodominant T cell epitopes of hen ovalbumin (OVA), a major egg allergen, to assess the therapeutic potential of PIT for food allergy, using the BALB/c mouse model. Methods Groups of mice were sensitized to OVA by repeated oral gavages, and subsequently administered with single or multiple synthetic peptides containing OVA T cell epitopes. Following the peptide administration period, all mice were orally challenged with high doses of OVA to elicit active anaphylaxis. Serum, spleen, and intestinal tissues were collected for the determination of immunoglobulin levels, cytokine secretions, and intestinal gene expression. Results Significantly lower anaphylactic scores were exhibited by mice that received multiple epitope-containing peptides, accompanied by lower serum histamine and OVA-specific IgE levels, compared with placebo-treated mice. Mechanistically, the quantification of cytokine secretions in splenocyte cultures revealed a T helper type 1-biased response (IFN-γ) in all peptide-treated mice to the detriment of a T helper type 2-response (IL-4). Interestingly, a similar cytokine expression profile was determined in intestinal tissues, accompanied by a pronounced mRNA expression of regulatory molecules TGF-β and forkhead box transcription factor 3 (FOXP3). These data suggest the activation of local repressive mechanisms mediated by subsets of regulatory T cells. Conclusion We demonstrated the therapeutic potential of PIT in a mouse model of food allergy model and provided evidence that mechanistic pathways entailing regulatory molecules TGF-β and FOXP3, stand as promising trails for the further understanding of peptide-based strategies for food allergy. Cite this as: M. Yang, C. Yang and Y. Mine, Clinical & Experimental Allergy, 2010 (40) 668–678. [ABSTRACT FROM AUTHOR]

Abstract: Several types of pesticides, such as organophosphates, phenoxyacetic acid, and carbamate have a high risk of affecting human health, causing allergic rhinitis and bronchial asthma-like diseases. We used our long-term sensitization method and a local lymph node assay to examine the allergic reactions caused by several types of pesticides. BALB/c mice were topically sensitized (9 times in 3 weeks), then challenged dermally or intratracheally with 2,4-D, BRP, or furathiocarb. One day post-challenge, the mice were processed to obtain biologic materials for use in assays of total IgE levels in serum and bronchoalveolar lavage fluid (BALF); differential cell counts and chemokine levels in BALF; lymphocyte counts and surface antigen expression on B-cells within regional lymph nodes (LNs); and, ex situ cytokine production by cells from these LNs. 2,4-D-induced immune responses characteristic of immediate-type respiratory reactions, as evidenced by increased total IgE levels in both serum and BALF; an influx of eosinophils, neutrophils, and chemokines (MCP-1, eotaxin, and MIP-1β) in BALF; increased surface antigen expression on B-cells IgE and MHC class II production) in both auricular and the lung-associated LNs; and increased Th2 cytokine production (IL-4, IL-5, IL-10, and IL-13) in both auricular and the lung-associated LN cells. In contrast, BRP and furathiocarb treatment yielded, at most, non-significant increases in all respiratory allergic parameters. BRP and furathiocarb induced marked proliferation of MHC Class II-positive B-cells and Th1 cytokines (IL-2, TNF-α, and IFN-γ) in only auricular LN cells. These results suggest that 2,4-D is a respiratory allergen and BRP and furathiocarb are contact allergens. As our protocol detected classified allergic responses to low-molecular-weight chemicals, it thus may be useful for detecting environmental chemical-related allergy. [Copyright &y& Elsevier]