Boswellia papyrifera (True frankincense tree) is a dry land tree which has economical and ecologi... more Boswellia papyrifera (True frankincense tree) is a dry land tree which has economical and ecological importance in the drylands. Although documenting and transmitting information about important dryland trees is crucial, such documents are lacking. Thus, this paper presents: (1) the botanical description, distribution and use of the species; (2) the causes, consequences and extent of degradation and (3) the restoration efforts that have been carried out in the Central Tigray - Northern Ethiopia. Boswellia papyrifera is a deciduous tree; it may grow up to 12m high or more with a rounded crown and yellow papery bark. Its product is frankincense; the white oleo-gum-resin exudate has a long history in human civilization. The natural oil contents and pleasant smell of frankincense caused it to be burned as incense in temple rituals and to be used as a base for perfumes and for medicinal purpose. However, its stock is shrinking and being fragmented rapidly due to human and non-human induc...
Cryptococcus neoformans glucuronoxylomannans (GXM) are capsular polysaccharides important for vir... more Cryptococcus neoformans glucuronoxylomannans (GXM) are capsular polysaccharides important for viru- lence in cryptococcosis. This study used dot enzyme assays (DEA) and enzyme-linked immunosorbent assays (ELISA) to determine the reactivity patterns of 21 murine monoclonal antibodies (MAbs) with structurally defined GXMs fromfive serotypes. The MAbs were categorized into eight groups on the basis of DEA andfive groups on the basis of
Journal of applied physiology (Bethesda, Md. : 1985), 2003
It has been reported that spaceflight conditions alter the immune system and resistance to infect... more It has been reported that spaceflight conditions alter the immune system and resistance to infection [Belay T, Aviles H, Vance M, Fountain K, and Sonnenfeld G. J Allergy Clin Immunol 170: 262-268, 2002; Hankins WR and Ziegelschmid JF. In: Biomedical Results of Apollo. Washington, DC: NASA, 1975, p. 43-81. (NASA Spec. Rep. SP-368)]. Ground-based models, including the hindlimb-unloading model, have become important tools for increasing understanding of how spaceflight conditions can influence physiology. The objective of the present study was to determine the effect of hindlimb unloading on the susceptibility of mice to Pseudomonas aeruginosa infection. Hindlimb-unloaded and control mice were subcutaneously infected with 1 LD50 of P. aeruginosa. Survival, bacterial organ load, and antibody and corticosterone levels were compared among the groups. Hindlimb unloading had detrimental effects for infected mice. Animals in the hindlimb-unloaded group, compared with controls, 1). showed sig...
Previous studies have demonstrated that resistance to infection is decreased in Swiss Webster fem... more Previous studies have demonstrated that resistance to infection is decreased in Swiss Webster female mice maintained in the hindlimb-unloading model (Aviles H, Belay T, Fountain K, Vance M, and Sonnenfeld G. J Appl Physiol 95: 73-80, 2003; Belay T, Aviles H, Vance M, Fountain K, and Sonnenfeld G. J Allergy Clin Immunol 110: 262-268, 2002). This is a model of some of the aspects of spaceflight conditions, including lack of load bearing on hindlimbs and a fluid shift to the head. Active hexose correlated compound (AHCC), extracted from Basidiomycete mushrooms, has been shown to induce enhancement of immune responses, including enhanced natural killer activity. In the present study, AHCC was orally administered to mice to determine whether the treatment could decrease immunosuppression and mortality of mice maintained in the hindlimb-unloaded model and infected with Klebsiella pneumoniae. The results of the present study showed that administration of AHCC by gavage for 1 wk (1 g/kg body wt) before suspension and throughout the 10-day suspension period yielded significant beneficial effects for the hindlimb-unloaded group, including 1). decreased mortality, 2). increased time to death, and 3). increased ability to clear bacteria. The results suggest that AHCC can decrease the deleterious effects of the hindlimb-unloading model on immunity and resistance to infection.
The rodent model of hindlimb unloading has been successfully used to simulate some of the effects... more The rodent model of hindlimb unloading has been successfully used to simulate some of the effects of space flight conditions. Previous studies have indicated that mice exposed to hindlimb-unloading conditions have decreased resistance to infections compared to restrained and normally housed control mice. The purpose of this study was to clarify the mechanisms involved in resistance to infection in this model by examining the effects of hindlimb unloading on the function of the immune system and its impact on the production of catecholamines. Female Swiss Webster mice were hindlimb-unloaded during 48 h and the function of the immune system was assessed in spleen and peritoneal cells immediately after this period. In addition, the kinetics of catecholamine production was measured throughout the hindlimb-unloading period. The function of the immune system was significantly suppressed in the hindlimb-unloaded group compared to restrained and normally housed control mice. Levels of catecholamines were increased in the hindlimb-unloaded group and peaked at 12 h following the commencement of unloading. These results suggest that physiological responses of mice are altered early after hindlimb unloading and that catecholamines may play a critical role in the modulation of the immune system. These changes may affect the ability of mice to resist infections.
The efficacy of liposomal amphotericin B bearing anticandidal antibodies (LAMB-Ab) was investigat... more The efficacy of liposomal amphotericin B bearing anticandidal antibodies (LAMB-Ab) was investigated in the treatment of systemic candidiasis in a murine model made neutropenic by an intraperitoneal injection of cyclophosphamide. Treatment with a single dose (0.6 mg amphotericin B kg-1 body weight) of LAMB-Ab resulted in an improved survival of neutropenic mice infected with Candida albicans compared to neutropenic mice treated with identical doses of liposomal amphotericin B or free amphotericin B.
Journal of Microbiology, Immunology and Infection, 2013
Genital infection by Chlamydia trachomatis (CT) is the most common bacterial sexually transmitted... more Genital infection by Chlamydia trachomatis (CT) is the most common bacterial sexually transmitted disease worldwide. The infection can cause serious reproductive health complications including pelvic inflammatory disease and infertility. Stress is implicated as a risk factor for various infections; however, its effect on Chlamydia genital infection and complications are unknown. We investigated the effect of cold-stress on resistance to Chlamydia genital infection, stress hormone production, and the functions of immune cells in a mouse model. Mice were infected intravaginally with CT after a 24-day cold-stress application. The course of infection was monitored by cervicovaginal swabbing for isolation of live Chlamydia in tissue culture. The production of stress hormones and cytokines in genital tracts, spleen or blood were assessed. Exposure of mice to 24-day stress resulted in: (a) increased susceptibility to Chlamydia genital infection and greater intensity of infection, (b) increased plasma or tissue noradrenaline and adrenaline levels, and (c) decreased mRNA and protein levels of major cytokines and chemokines in the spleen and genital tract. These results suggest that cold-induced stress induces the production of catecholamines, which may play a critical role in the modulation of the immune system leading to increased susceptibility and greater intensity of Chlamydia genital infection that could promote the development of complications.
Hindlimb unloading is a ground-based model that simulates some of the aspects of spaceflight cond... more Hindlimb unloading is a ground-based model that simulates some of the aspects of spaceflight conditions, including lack of load bearing on hindlimbs and a fluid shift to the head. It has been shown that treatment with active hexose correlated compound (AHCC) restores resistance to infection in mice maintained under hindlimb-unloading conditions. The present study was designed to clarify the mechanisms by which AHCC enhances resistance to infection in this model. We hypothesized that oral administration of AHCC will enhance the function of the immune system, which could lead to the increased resistance to infection observed in this model. AHCC or the excipient was orally administered to mice, and the function of the immune system was assessed in spleen and peritoneal cells isolated from those groups. The results of the present study showed that administration of AHCC for 1 wk before and throughout the second day of the hindlimb-unloading period enhanced the function of the immune system assessed by spleen cell proliferation and cytokine production in spleens and nitric oxide and cytokine production in peritoneal cells. These findings suggest that AHCC can be used as a potent immunoenhancer, especially in cases in which the immune system is suppressed by any condition, including diseases such as human immunodeficiency virus infection and cancer.
Boswellia papyrifera (True frankincense tree) is a dry land tree which has economical and ecologi... more Boswellia papyrifera (True frankincense tree) is a dry land tree which has economical and ecological importance in the drylands. Although documenting and transmitting information about important dryland trees is crucial, such documents are lacking. Thus, this paper presents: (1) the botanical description, distribution and use of the species; (2) the causes, consequences and extent of degradation and (3) the restoration efforts that have been carried out in the Central Tigray - Northern Ethiopia. Boswellia papyrifera is a deciduous tree; it may grow up to 12m high or more with a rounded crown and yellow papery bark. Its product is frankincense; the white oleo-gum-resin exudate has a long history in human civilization. The natural oil contents and pleasant smell of frankincense caused it to be burned as incense in temple rituals and to be used as a base for perfumes and for medicinal purpose. However, its stock is shrinking and being fragmented rapidly due to human and non-human induc...
Cryptococcus neoformans glucuronoxylomannans (GXM) are capsular polysaccharides important for vir... more Cryptococcus neoformans glucuronoxylomannans (GXM) are capsular polysaccharides important for viru- lence in cryptococcosis. This study used dot enzyme assays (DEA) and enzyme-linked immunosorbent assays (ELISA) to determine the reactivity patterns of 21 murine monoclonal antibodies (MAbs) with structurally defined GXMs fromfive serotypes. The MAbs were categorized into eight groups on the basis of DEA andfive groups on the basis of
Journal of applied physiology (Bethesda, Md. : 1985), 2003
It has been reported that spaceflight conditions alter the immune system and resistance to infect... more It has been reported that spaceflight conditions alter the immune system and resistance to infection [Belay T, Aviles H, Vance M, Fountain K, and Sonnenfeld G. J Allergy Clin Immunol 170: 262-268, 2002; Hankins WR and Ziegelschmid JF. In: Biomedical Results of Apollo. Washington, DC: NASA, 1975, p. 43-81. (NASA Spec. Rep. SP-368)]. Ground-based models, including the hindlimb-unloading model, have become important tools for increasing understanding of how spaceflight conditions can influence physiology. The objective of the present study was to determine the effect of hindlimb unloading on the susceptibility of mice to Pseudomonas aeruginosa infection. Hindlimb-unloaded and control mice were subcutaneously infected with 1 LD50 of P. aeruginosa. Survival, bacterial organ load, and antibody and corticosterone levels were compared among the groups. Hindlimb unloading had detrimental effects for infected mice. Animals in the hindlimb-unloaded group, compared with controls, 1). showed sig...
Previous studies have demonstrated that resistance to infection is decreased in Swiss Webster fem... more Previous studies have demonstrated that resistance to infection is decreased in Swiss Webster female mice maintained in the hindlimb-unloading model (Aviles H, Belay T, Fountain K, Vance M, and Sonnenfeld G. J Appl Physiol 95: 73-80, 2003; Belay T, Aviles H, Vance M, Fountain K, and Sonnenfeld G. J Allergy Clin Immunol 110: 262-268, 2002). This is a model of some of the aspects of spaceflight conditions, including lack of load bearing on hindlimbs and a fluid shift to the head. Active hexose correlated compound (AHCC), extracted from Basidiomycete mushrooms, has been shown to induce enhancement of immune responses, including enhanced natural killer activity. In the present study, AHCC was orally administered to mice to determine whether the treatment could decrease immunosuppression and mortality of mice maintained in the hindlimb-unloaded model and infected with Klebsiella pneumoniae. The results of the present study showed that administration of AHCC by gavage for 1 wk (1 g/kg body wt) before suspension and throughout the 10-day suspension period yielded significant beneficial effects for the hindlimb-unloaded group, including 1). decreased mortality, 2). increased time to death, and 3). increased ability to clear bacteria. The results suggest that AHCC can decrease the deleterious effects of the hindlimb-unloading model on immunity and resistance to infection.
The rodent model of hindlimb unloading has been successfully used to simulate some of the effects... more The rodent model of hindlimb unloading has been successfully used to simulate some of the effects of space flight conditions. Previous studies have indicated that mice exposed to hindlimb-unloading conditions have decreased resistance to infections compared to restrained and normally housed control mice. The purpose of this study was to clarify the mechanisms involved in resistance to infection in this model by examining the effects of hindlimb unloading on the function of the immune system and its impact on the production of catecholamines. Female Swiss Webster mice were hindlimb-unloaded during 48 h and the function of the immune system was assessed in spleen and peritoneal cells immediately after this period. In addition, the kinetics of catecholamine production was measured throughout the hindlimb-unloading period. The function of the immune system was significantly suppressed in the hindlimb-unloaded group compared to restrained and normally housed control mice. Levels of catecholamines were increased in the hindlimb-unloaded group and peaked at 12 h following the commencement of unloading. These results suggest that physiological responses of mice are altered early after hindlimb unloading and that catecholamines may play a critical role in the modulation of the immune system. These changes may affect the ability of mice to resist infections.
The efficacy of liposomal amphotericin B bearing anticandidal antibodies (LAMB-Ab) was investigat... more The efficacy of liposomal amphotericin B bearing anticandidal antibodies (LAMB-Ab) was investigated in the treatment of systemic candidiasis in a murine model made neutropenic by an intraperitoneal injection of cyclophosphamide. Treatment with a single dose (0.6 mg amphotericin B kg-1 body weight) of LAMB-Ab resulted in an improved survival of neutropenic mice infected with Candida albicans compared to neutropenic mice treated with identical doses of liposomal amphotericin B or free amphotericin B.
Journal of Microbiology, Immunology and Infection, 2013
Genital infection by Chlamydia trachomatis (CT) is the most common bacterial sexually transmitted... more Genital infection by Chlamydia trachomatis (CT) is the most common bacterial sexually transmitted disease worldwide. The infection can cause serious reproductive health complications including pelvic inflammatory disease and infertility. Stress is implicated as a risk factor for various infections; however, its effect on Chlamydia genital infection and complications are unknown. We investigated the effect of cold-stress on resistance to Chlamydia genital infection, stress hormone production, and the functions of immune cells in a mouse model. Mice were infected intravaginally with CT after a 24-day cold-stress application. The course of infection was monitored by cervicovaginal swabbing for isolation of live Chlamydia in tissue culture. The production of stress hormones and cytokines in genital tracts, spleen or blood were assessed. Exposure of mice to 24-day stress resulted in: (a) increased susceptibility to Chlamydia genital infection and greater intensity of infection, (b) increased plasma or tissue noradrenaline and adrenaline levels, and (c) decreased mRNA and protein levels of major cytokines and chemokines in the spleen and genital tract. These results suggest that cold-induced stress induces the production of catecholamines, which may play a critical role in the modulation of the immune system leading to increased susceptibility and greater intensity of Chlamydia genital infection that could promote the development of complications.
Hindlimb unloading is a ground-based model that simulates some of the aspects of spaceflight cond... more Hindlimb unloading is a ground-based model that simulates some of the aspects of spaceflight conditions, including lack of load bearing on hindlimbs and a fluid shift to the head. It has been shown that treatment with active hexose correlated compound (AHCC) restores resistance to infection in mice maintained under hindlimb-unloading conditions. The present study was designed to clarify the mechanisms by which AHCC enhances resistance to infection in this model. We hypothesized that oral administration of AHCC will enhance the function of the immune system, which could lead to the increased resistance to infection observed in this model. AHCC or the excipient was orally administered to mice, and the function of the immune system was assessed in spleen and peritoneal cells isolated from those groups. The results of the present study showed that administration of AHCC for 1 wk before and throughout the second day of the hindlimb-unloading period enhanced the function of the immune system assessed by spleen cell proliferation and cytokine production in spleens and nitric oxide and cytokine production in peritoneal cells. These findings suggest that AHCC can be used as a potent immunoenhancer, especially in cases in which the immune system is suppressed by any condition, including diseases such as human immunodeficiency virus infection and cancer.
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Papers by Tesfaye Belay