African swine fever virus (ASFV) is the causative agent of African swine fever that is the signif... more African swine fever virus (ASFV) is the causative agent of African swine fever that is the significant disease of domestic pigs, with high rates of mortality. ASFV is double-stranded DNA virus whose genes encode some proteins that are implicated in the suppression of host immune response. In this study, we have modeled in vivo infection of ASFV for determination of interferon (IFN) status in infected pigs. We measured the level of IFN-α, -β and -γ by enzyme-linked immunosorbent assay and showed that the level of IFN-α sharply decreased during infection. Unlike IFN-α, the level of IFN-β and -γ increased from the 2nd and 4th days post-infection, respectively. Also, we analyzed the population dynamics of peripheral white blood cells of infected pigs due to their important role in host immune system. We showed that the atypical lymphocytes appeared after short time of infection and this result is in accordance with our previous study done in vitro. At the last day of infection about 50% of the total white blood cells were destroyed, and the remaining cells were represented mainly by small-sized lymphocytes, reactive lymphocytes and lymphoblasts.
Polyploidization is one of the most dramatic changes occurring within cell genome owing to variou... more Polyploidization is one of the most dramatic changes occurring within cell genome owing to various reasons including under many viral infections. We examined the impact of herpes simplex virus-1 (HSV-1) on SK-N-MC human neuroblastoma cell line. The infected cells were followed from 6 hours up to 96 hours post infection (hpi). A large number of polyploid cells with giant nuclei was observed under the influence of HSV-1 at 24 hpi with the DNA content of 32c to 64c or more, in comparison with control SK-N-MC cells that were characterized by relatively moderate values of ploidy, i.e. 8с to 16с (where 1c is the haploid amount of nuclear DNA found in normal diploid populations in G0/G1). After 48-96 hpi, the population of polyploid cells with giant nuclei decreased to the benchmark level. The SK-NMC cells infected with HSV-1 for 24 hours were stained with gallocyanine and monitored for cytological features. The infected cells underwent virus induced cellcell and nuclei fusion with the formation of dense nuclei syncytium. The metabolic activity of HSV-1 infected cells was higher in both nuclei and nucleoli when compared to control cells.
OBJECTIVE To identify the effect of brain extracts from people of different age groups on possibl... more OBJECTIVE To identify the effect of brain extracts from people of different age groups on possible changes in cell physiology and behavior in vitro. MATERIAL AND METHODS Human frontal cortical segments were obtained 12-24 hours after autopsy. Brain tissue extract was taken from young people who died at age of 22.5±2.7 years and old people at 80.9±3.0 years. SK-N-MC human neuroblastoma cells were cultured in a medium containing 50 mg/ml of brain tissue extracts; blood serum (50 mg/ml) from healthy people was used as a control. Procedures for cytophotometry of DNA and acidic proteins and polarized light microscopy were used. RESULTS A short-term decrease in acidic protein levels in the nucleus and nucleolus was found to be affected by brain extracts from old people. There were higher cytoplasmic acidic protein levels. At the same time, the same indicators generally remained noticeably unchanged under the influence of brain extracts from young people. There were also simultaneous pronounced changes in cell morphology and behavior in vitro; namely, neuronal cell processes became shorter and their proliferative activity increased, which was not least a result of the unblocking of cells in the G2 phase under the influence of brain extracts from old people. CONCLUSION The factors that accelerate cell proliferation in vitro accumulate in the human brain with age. Simultaneously with the acceleration of cell proliferation, there are changes in cell metabolic activity and morphology.
We analyzed the connection of changes in nucleus ploidy with changes in nucleolar apparatus of NI... more We analyzed the connection of changes in nucleus ploidy with changes in nucleolar apparatus of NIH 3T3 cells. The quantity of nucleoli does not depend on the quantity of nucleolar DNA, but instead depends on euploidy: the majority of euploid cells have 1–3 nucleoli. The quantity of DNA in the nucleolus is correlated with the quantity of nucleolar DNA, and does not depend on ploidy changes. The nucleolar area has a tendency to increase in line with an increase in their numbers in the nucleus. The relationship of the quantity of DNA in the nucleolus with that of the nucleus is stable. During the process of increase in the number of nucleoli in a nucleus, there is a corresponding decrease in the quantity of DNA in each nucleolus, and there is likewise no increase in the sum of nucleolar DNA. The ratio of sums of the nucleolar perimeters to nuclear perimeter is a significant factor, which increases linearly along with an increase in the number of nucleoli in a nucleus.
Glomerulonephritis due to African swine fever (ASF) is well documented. However, there is absence... more Glomerulonephritis due to African swine fever (ASF) is well documented. However, there is absence of good understanding of mechanisms involved in the development of pathology development. This study examines glomerulonephritis in association with acute infection induced by II genotype (Georgia 2007) of ASF virus. Taken together, the results of urinary analysis and the renal histological analysis led to the diagnosis of diffuse endocapillary proliferative glomerulonephritis with severe tubular injury associated with acute ASF (Georgia 2007). According to the pathogenesis, we have found that the diffuse endocapillary proliferative glomerulonephritis associated with the acute ASF develops with a delay of one to two days compared to development of hemophagocytic lymphohistiocytosis. The diagnosis of endocapillary proliferative glomerulonephritis confirms the characteristic of pathological changes in the composition of urine and urine sediment. The development of acute proliferative glomerulonephritis begins at 3 dpi, and finished at 4–6 dpi with the development of tubular necrosis. Our study demonstrates local macrophage proliferation. Local proliferation may be an important mechanism for amplifying macrophage-mediated renal injury. We have shown that the development of diffuse acute proliferative glomerulonephritis during ASF does not coincide with the presence of the virus in the blood or kidney tissues, but coincides with the developmental of ASFV derived hemophagocytic lymphohistiocytosis. The development of hemophagocytic lymphonocytosis also begins at least at 2–3 dpi and continues up to the terminal stage of the disease.
African swine fever virus (ASFV) is the causative agent of African swine fever that is the signif... more African swine fever virus (ASFV) is the causative agent of African swine fever that is the significant disease of domestic pigs, with high rates of mortality. ASFV is double-stranded DNA virus whose genes encode some proteins that are implicated in the suppression of host immune response. In this study, we have modeled in vivo infection of ASFV for determination of interferon (IFN) status in infected pigs. We measured the level of IFN-α, -β and -γ by enzyme-linked immunosorbent assay and showed that the level of IFN-α sharply decreased during infection. Unlike IFN-α, the level of IFN-β and -γ increased from the 2nd and 4th days post-infection, respectively. Also, we analyzed the population dynamics of peripheral white blood cells of infected pigs due to their important role in host immune system. We showed that the atypical lymphocytes appeared after short time of infection and this result is in accordance with our previous study done in vitro. At the last day of infection about 50% of the total white blood cells were destroyed, and the remaining cells were represented mainly by small-sized lymphocytes, reactive lymphocytes and lymphoblasts.
Polyploidization is one of the most dramatic changes occurring within cell genome owing to variou... more Polyploidization is one of the most dramatic changes occurring within cell genome owing to various reasons including under many viral infections. We examined the impact of herpes simplex virus-1 (HSV-1) on SK-N-MC human neuroblastoma cell line. The infected cells were followed from 6 hours up to 96 hours post infection (hpi). A large number of polyploid cells with giant nuclei was observed under the influence of HSV-1 at 24 hpi with the DNA content of 32c to 64c or more, in comparison with control SK-N-MC cells that were characterized by relatively moderate values of ploidy, i.e. 8с to 16с (where 1c is the haploid amount of nuclear DNA found in normal diploid populations in G0/G1). After 48-96 hpi, the population of polyploid cells with giant nuclei decreased to the benchmark level. The SK-NMC cells infected with HSV-1 for 24 hours were stained with gallocyanine and monitored for cytological features. The infected cells underwent virus induced cellcell and nuclei fusion with the formation of dense nuclei syncytium. The metabolic activity of HSV-1 infected cells was higher in both nuclei and nucleoli when compared to control cells.
OBJECTIVE To identify the effect of brain extracts from people of different age groups on possibl... more OBJECTIVE To identify the effect of brain extracts from people of different age groups on possible changes in cell physiology and behavior in vitro. MATERIAL AND METHODS Human frontal cortical segments were obtained 12-24 hours after autopsy. Brain tissue extract was taken from young people who died at age of 22.5±2.7 years and old people at 80.9±3.0 years. SK-N-MC human neuroblastoma cells were cultured in a medium containing 50 mg/ml of brain tissue extracts; blood serum (50 mg/ml) from healthy people was used as a control. Procedures for cytophotometry of DNA and acidic proteins and polarized light microscopy were used. RESULTS A short-term decrease in acidic protein levels in the nucleus and nucleolus was found to be affected by brain extracts from old people. There were higher cytoplasmic acidic protein levels. At the same time, the same indicators generally remained noticeably unchanged under the influence of brain extracts from young people. There were also simultaneous pronounced changes in cell morphology and behavior in vitro; namely, neuronal cell processes became shorter and their proliferative activity increased, which was not least a result of the unblocking of cells in the G2 phase under the influence of brain extracts from old people. CONCLUSION The factors that accelerate cell proliferation in vitro accumulate in the human brain with age. Simultaneously with the acceleration of cell proliferation, there are changes in cell metabolic activity and morphology.
We analyzed the connection of changes in nucleus ploidy with changes in nucleolar apparatus of NI... more We analyzed the connection of changes in nucleus ploidy with changes in nucleolar apparatus of NIH 3T3 cells. The quantity of nucleoli does not depend on the quantity of nucleolar DNA, but instead depends on euploidy: the majority of euploid cells have 1–3 nucleoli. The quantity of DNA in the nucleolus is correlated with the quantity of nucleolar DNA, and does not depend on ploidy changes. The nucleolar area has a tendency to increase in line with an increase in their numbers in the nucleus. The relationship of the quantity of DNA in the nucleolus with that of the nucleus is stable. During the process of increase in the number of nucleoli in a nucleus, there is a corresponding decrease in the quantity of DNA in each nucleolus, and there is likewise no increase in the sum of nucleolar DNA. The ratio of sums of the nucleolar perimeters to nuclear perimeter is a significant factor, which increases linearly along with an increase in the number of nucleoli in a nucleus.
Glomerulonephritis due to African swine fever (ASF) is well documented. However, there is absence... more Glomerulonephritis due to African swine fever (ASF) is well documented. However, there is absence of good understanding of mechanisms involved in the development of pathology development. This study examines glomerulonephritis in association with acute infection induced by II genotype (Georgia 2007) of ASF virus. Taken together, the results of urinary analysis and the renal histological analysis led to the diagnosis of diffuse endocapillary proliferative glomerulonephritis with severe tubular injury associated with acute ASF (Georgia 2007). According to the pathogenesis, we have found that the diffuse endocapillary proliferative glomerulonephritis associated with the acute ASF develops with a delay of one to two days compared to development of hemophagocytic lymphohistiocytosis. The diagnosis of endocapillary proliferative glomerulonephritis confirms the characteristic of pathological changes in the composition of urine and urine sediment. The development of acute proliferative glomerulonephritis begins at 3 dpi, and finished at 4–6 dpi with the development of tubular necrosis. Our study demonstrates local macrophage proliferation. Local proliferation may be an important mechanism for amplifying macrophage-mediated renal injury. We have shown that the development of diffuse acute proliferative glomerulonephritis during ASF does not coincide with the presence of the virus in the blood or kidney tissues, but coincides with the developmental of ASFV derived hemophagocytic lymphohistiocytosis. The development of hemophagocytic lymphonocytosis also begins at least at 2–3 dpi and continues up to the terminal stage of the disease.
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Papers by Zaven Karalyan