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Yujiang Zhang - One of the best experts on this subject based on the ideXlab platform.
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Dynamics of Yersinia pestis and Its Antibody Response in Great Gerbils (Rhombomys opimus) by Subcutaneous Infection
2016Co-Authors: Yujiang Zhang, Qiguo Wang, Azhati Rehemu, Xinhui Wang, Weiwei Meng, Xiang Dai, Tao Luo, Abulimiti Maituohuti, Yujun Cui, Rong GuoAbstract:Background: Rhombomys opimus (great gerbil) is a reservoir of Yersinia pestis in the natural plague foci of Central Asia. Great gerbils are highly resistant to Y. pestis infection. The coevolution of great gerbils and Y. pestis is believed to play an important role in the plague epidemics in Central Asia plague foci. However, the dynamics of Y. pestis infection and the corresponding antibody response in great gerbils have not been evaluated. In this report, animal experiments were employed to investigate the bacterial load in both the liver and spleen of infected great gerbils. The dynamics of the antibody response to the F1 capsule antigen of Y. pestis was also determined. Methodology: Captured great gerbils that tested negative for both anti-F1 antibodies and bacterial isolation were infected subcutaneously with different doses (105 to 1011 CFU) of a Y. pestis strain isolated from a live great gerbil during routine plague surveillance in the Junggar Basin, Xinjiang, China. The clinical manifestations, changes in body weight, anal temperature, and gross anatomy of the infected animals were observed. The blood cell count, bacterial load, and anti-F1 antibody titers were determined at different time points after infection using a blood analyzer, plate counts, and an indirect hemagglutination assay, respectively. Conclusions/Significance: The dynamics of bacterial load and the anti-F1 antibody concentration in great gerbils are highly variable among individuals. The Y. pestis infection in great gerbils could persist as long as 15 days. They act as a
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transmission efficiency of the plague pathogen y pestis by the flea xenopsylla skrjabini to mice and great gerbils
Parasites & Vectors, 2015Co-Authors: Yujiang Zhang, Qiguo Wang, Hongjian Chen, Kemei Wu, Azhati Rehemu, Xiaotao Yu, Ruifu Yang, Xinhui Wang, Weiwei Meng, Yajun SongAbstract:Background Plague, a zoonotic disease caused by Yersinia pestis, is characterized by its ability to persist in the plague natural foci. Junggar Basin plague focus was recently identified in China, with Rhombomys opimus (great gerbils) and Xenopsylla skrjabini as the main reservoir and vector for plague. No transmission efficiency data of X. skrjabini for Y. pestis is available till now.
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Study on the spatial distribution and related risks of Rhombomys opimus, based on the ecological niche modeling in Junggar Basin, Xinjiang
Zhonghua liu xing bing xue za zhi = Zhonghua liuxingbingxue zazhi, 2014Co-Authors: Mei Wang, Qiguo Wang, Tao Luo, Jian Zhao, Ti Azha, Yujiang ZhangAbstract:Objective In order to understand the distribution of the host animals in Junggar Basin,this study intended to map the spatial distribution and identifying the risk of Rhombomys opimus in the framework of ecological niche theory based on the "3S" technology.Methods Data on Rhombomys opimus was obtained through a series of field surveys.Environmental variables were achieved through data from Remote Sensing.Maxent modeling was built to map the potential distribution of Rhombomys opimus,with its risks identified.Results The prediction model showed ideal accuracy,with the AUC value as 0.968.Probability of Maximum Youden Index was defined as the threshold being used.The sensitivity and specificity showed as 91.4％ and 63.3％,respectively.The accuracy was 73.8％,and the Kappa coefficient was 0.495.The positive predictive value was 59.7％.The negative predictive value was 92.6％.The predicted high risk area was 37 304 km2,with 6.2％ in the whole area,distributed in 18 counties,including Changji Hui Autonomous Prefecture,Urumqi,Karamay and so on.The number of people under high risk would come about 120 000,scattering in the areas of 261 square kilometers.Conclusion It was feasible to predict the potential distribution of Rhombomys opimus based on the ecological niche theory as well as environmental variables derived from data through remote sensing.More specific high-risk areas could be identified under this technique so as to guide the monitoring programs. Key words: Plague foci; Ecological niche modeling; Geographical information system
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Dynamics of Yersinia pestis and its antibody response in great gerbils (Rhombomys opimus) by subcutaneous infection.
PloS one, 2012Co-Authors: Yujiang Zhang, Qiguo Wang, Azhati Rehemu, Xinhui Wang, Weiwei Meng, Xiang Dai, Tao Luo, Abulimiti Maituohuti, Yujun Cui, Rong GuoAbstract:Background Rhombomys opimus (great gerbil) is a reservoir of Yersinia pestis in the natural plague foci of Central Asia. Great gerbils are highly resistant to Y. pestis infection. The coevolution of great gerbils and Y. pestis is believed to play an important role in the plague epidemics in Central Asia plague foci. However, the dynamics of Y. pestis infection and the corresponding antibody response in great gerbils have not been evaluated. In this report, animal experiments were employed to investigate the bacterial load in both the liver and spleen of infected great gerbils. The dynamics of the antibody response to the F1 capsule antigen of Y. pestis was also determined. Methodology Captured great gerbils that tested negative for both anti-F1 antibodies and bacterial isolation were infected subcutaneously with different doses (105 to 1011 CFU) of a Y. pestis strain isolated from a live great gerbil during routine plague surveillance in the Junggar Basin, Xinjiang, China. The clinical manifestations, changes in body weight, anal temperature, and gross anatomy of the infected animals were observed. The blood cell count, bacterial load, and anti-F1 antibody titers were determined at different time points after infection using a blood analyzer, plate counts, and an indirect hemagglutination assay, respectively. Conclusions/Significance The dynamics of bacterial load and the anti-F1 antibody concentration in great gerbils are highly variable among individuals. The Y. pestis infection in great gerbils could persist as long as 15 days. They act as an appropriate reservoir for plague in the Junggar Basin, which is part of the natural plague foci in Central Asia. The dynamics of the Y. pestis susceptibility of great gerbil will improve the understanding of its variable resistance, which would facilitate the development of more effective countermeasures for controlling plague epidemics in this focus.
K A Rogovin - One of the best experts on this subject based on the ideXlab platform.
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long term dynamics of fecal corticosterone in male great gerbils Rhombomys opimus licht effects of environment and social demography
Physiological and Biochemical Zoology, 2008Co-Authors: K A Rogovin, I E Kolosova, Jan A Randall, M P MoshkinAbstract:Abstract We examined the relationship among seasonal characteristics of climate, food, and population demography (social structure) and fecal corticosterone (CORT) concentrations over 6 yr in adult males of an arid‐adapted species, the great gerbil (Rhombomys opimus Licht., Gerbillidae, Rodentia), as a measure of chronic stress in high, low, and recovering population densities. Results showed yearly differences in the seasonal means of CORT, with the highest concentrations in the year of the highest population density. Analysis of year‐specific relationships revealed a positive correlation between mean CORT and total precipitation in January and February and a negative correlation with precipitation in March. In the beginning of spring, when gerbils were in maximum reproductive effort, CORT correlated positively with the saturation of burrow systems and with the number of adult females with an adult male. A linear stepwise regression of CORT in individual males in spring seasons of all 6 yr combined after...
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Social influences on the morpho-physiological characteristics of young males in groups of great gerbils Rhombomys opimus in a high density population: a case study
2006Co-Authors: K A Rogovin, A J Randall, Y N Vasilieva, M P MoshkinAbstract:In a non-breeding, high density population of great gerbil (Rhombomys opimus Licht) (Bukhara region, Uzbekistan) we studied the dependence of stress and sex hormone concentrations, size of the mid-ventral gland and body mass of young males on presence of adult gerbils (≥1 year old) in social groups. Corticosterone and testosterone in fecal samples collected in the field from young males in fall 1999 were analyzed by non-invasive radioimmunoassay. Gerbil groups with adults were larger in size than groups without adults, so the effect of adults on juveniles can not be considered independently from the group size effect per se. Presence of adults positively affected concentration of fecal corticosterone and suppressed maturation of juvenile males estimated by the smaller size of the mid-ventral gland as an androgen-dependent organ, but at the same time accelerated their growth. Thus a naturally occurring social environment can influence development of morpho-physiological characteristics of young males.
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alarm signals of the great gerbil acoustic variation by predator context sex age individual and family group
Journal of the Acoustical Society of America, 2005Co-Authors: Jan A Randall, Brenda Mccowan, Kellie C Collins, Stacie L Hooper, K A RogovinAbstract:The great gerbil, Rhombomys opinus, is a highly social rodent that usually lives in family groups consisting of related females, their offspring, and an adult male. The gerbils emit alarm vocalizations in the presence of diverse predators with different hunting tactics. Alarm calls were recorded in response to three predators, a monitor lizard, hunting dog, and human, to determine whether the most common call type, the rhythmic call, is functionally referential with regard to type of predator. Results show variation in the alarm calls of both adults and subadults with the type of predator. Discriminant function analysis classified an average of 70% of calls to predator type. Call variation, however, was not limited to the predator context, because signal structure also differed by sex, age, individual callers, and family groups. These variations illustrate the flexibility of the rhythmic alarm call of the great gerbil and how it might have multiple functions and communicate in multiple contexts. Three alarm calls, variation in the rhythmic call, and vibrational signals generated from foot-drumming provide the gerbils with a varied and multi-channel acoustic repertoire.
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Flexible social structure of a desert rodent, Rhombomys opimus: philopatry, kinship, and ecological constraints
Behavioral Ecology, 2005Co-Authors: Jan A Randall, K A Rogovin, Patricia G. Parker, John A. EimesAbstract:We tested hypotheses based on philopatry, kinship, and ecological constraints to explain sociality in a semifossorial desert rodent, the great gerbil, Rhombomys opimus. Data were collected in the field in Uzbekistan in the spring and fall of 1996 and 1998–2004. Population densities fluctuated dramatically with high turnover in both males and females to reveal that dispersal and social structure were density dependent. Fewer gerbils dispersed at higher densities and members of family groups dispersed together. A majority of females lived in groups at high densities, but as population densities declined, proportionally more females were solitary. DNA analysis revealed that group-living females were genetically similar, whereas solitary females visited by the same male, as well as adult males and females in the same family group, were usually not genetically similar. Reproductive success as measured by the number of emergent pups and survival of juveniles during the summer drought was not related to group size or whether females were philopatric. A majority of females in family groups reproduced, and all females engaged in cooperative behaviors. We accepted three hypotheses to explain fluctuations in group formation in the great gerbil: variation in food abundance and distribution, habitat saturation, and kinship. We conclude that great gerbils are facultatively social. Flexible social behavior may be adaptive in unpredictable desert conditions. Females live solitarily under conditions of limited food and high mortality that disrupt social behavior and group formation and share territories with female kin under favorable conditions for survival and reproduction when kin groups can be maintained. Males adjust to the distribution of females. Key words: desert, gerbil, philopatry, Rhombomys opimus, social. [Behav Ecol]
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PREDATION ON A SOCIAL DESERT RODENT, Rhombomys OPIMUS: EFFECT OF GROUP SIZE, COMPOSITION, AND LOCATION
Journal of Mammalogy, 2004Co-Authors: K A Rogovin, Jan A Randall, Irina Kolosova, M P MoshkinAbstract:Predation can provide both positive and negative effects on formation of social groups in rodents. On the basis of observational data of predation by the desert monitor lizard (Varanus griseus caspius) on the great gerbil (Rhombomys opimus), a social rodent of desert Central Asia, we predicted that in a year after a peak in prey density, when the abundance of terrestrial predators is still high, the group mode of life of a prey species might become disadvantageous. Social groups could advertise themselves and attract predators. We therefore hypothesized that the probability of predation would be higher for gerbils in outlying social groups than in groups closely associated with each other, in larger compared with smaller groups, and in groups with an active adult male compared with solitary females with no resident male. We also analyzed whether the survival of gerbils and the stress levels in adult and juvenile males were related to frequency of visits by monitor lizards at gerbil colonies (isolated systems of burrows used by gerbil groups of any size), distance between colonies, and size of social groups. We found that frequency of visits by the monitor lizard depended on distance to the nearest neighboring colony. The more distant the gerbil colony, the more visits by the lizard and the lower the survival of juveniles. We also found a positive correlation between concentration of fecal corticosterone in young males and frequency of monitor lizard visits at colonies. This pattern was not as pronounced in adult males. Results did not support the hypothesis that larger groups would have higher predation because frequency of predator visits, distances to the nearest occupied colonies, and survival of juveniles did not correlate significantly with the size of family groups. There was no difference in survival of juveniles in colonies occupied by single females compared with colonies in which an adult male was present. These results suggest that there is a possible trade-off between competing strategies of antipredator behavior and that factors other than predation are influencing gerbil survival.
Qiguo Wang - One of the best experts on this subject based on the ideXlab platform.
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Dynamics of F1 antibody responses to Yersinia pestis infection in Rhombomys opimus
Zhonghua yu fang yi xue za zhi [Chinese journal of preventive medicine], 2017Co-Authors: Weiwei Meng, Qiguo Wang, Xinhui Wang, Tao Luo, Abulikemu, Burenmingde, Azati, Abulimiti, Rong GuoAbstract:Objective: To observe the dynamics of antibody response in great gerbils infected with Yersinia pestis in experiment. Method: A total of 211 great gerbils were captured in the southern margin of plague natural focus of Junggar Basin of the Xinjiang Uygur Autonomous Region in 2011. Among them, there were 167 great gerbils without infection of Y. pestis and 44 great gerbils infected by Y.pestis. Y.pestis No. 2504 was employed for this experimental strain, which was strong toxic strain with negativity in the reduction experiment of nitrate. 35 great gerbils without the infection of Y. pestis were divided randomly and averagely into 7 groups including 6 experimental groups and 1 control group. Great gerbils in the 1st to 6th experimental groups were exposed first with 1 × 10(6)-1 × 10(11) CFU/ml of bacterial fluid with 10 times of gradient dilution; groin areas of great gerbils in the control group were injected subcutaneously with physiological saline; and the amount of infection was all 1 ml. 17 great gerbils infected with Y. pestis and the first detection of F1-antibody titer in 1∶256-1∶4 096 were grouped according to F1-antibody titer: group 1∶4 096 (n=4), group 1∶2 048 (n=4), group 1∶1 024 (n=3), group 1∶512 (n=3) and group 1∶256 (n=3); and blood in caudal regions was collected in asepsis for the detection of F1-antibody, with a total of 5 times. 9 great gerbils which were selected from the remaining great gerbils infected with Y. pestis and detected F1-antibody negative 2 times were exposed 1×10(6) CFU/ml of bacterial fluid for the second infection, with the amount of infection being 1 ml. Blood in caudal regions of great gerbils after the first and second infection were collected for the detection of plague F1-antibody on the 3rd, 5th, 7th, 15th, 30th, 60th, 90th and 120th day after infection. Declined regression models for great gerbils' antibodies were established with unary linear regression equation; declined change diagrams for the antibodies were drawn to observe the declined F1-antibody after great gerbils were exposed to Y. pestis. Results: In great gerbils with the first infection of Y. pestis, antibodies were detected in the 1 × 10(6)-1 × 10(8) CFU/ml of group on the 30th, 15th and 15th day, respectively; the positive rates of antibody were 1/4, 3/4 and 4/5, respectively; the group 1×10(7) and 1× 10(8) CFU/ml reached to the highest antibody titer with 1∶256 on the 120th day; antibodies were revealed in the group 1×10(9), 1×10(10) and 1×10(11) CFU/ml from the 5th to 7th day when the seroconversion of all antibodies was observed; group 1×10(11) CFU/ml reached to the highest antibody titer on the 120th day with 1∶4 096. In the great gerbils with the second exposure to Y.pestis, positive antibodies were detected on the 3rd day with the positive rate being 2/9; and the highest antibody titer with 1∶2 048 was noted on the 90th day. Unary linear regression equation of declined F1 antibody of great gerbils was y=0.045x- 0.321 (F=115.40, P< 0.001), and the shortest duration for F1-antibody titer declining from 1∶4 096 to 0 was 140 d and the longest duration 200 d. Conclusion: Great gerbils infected with the high concentration of Y. pestis fluid show shorter duration in producing F1-antibody, the antibody positive rate is also higher, and the highest antibody titer can reach 1∶4 096. The great gerbils could hold the plague F1 antibodies for a long time which was about 140 to 200 days from the highest titer.
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Dynamics of Yersinia pestis and Its Antibody Response in Great Gerbils (Rhombomys opimus) by Subcutaneous Infection
2016Co-Authors: Yujiang Zhang, Qiguo Wang, Azhati Rehemu, Xinhui Wang, Weiwei Meng, Xiang Dai, Tao Luo, Abulimiti Maituohuti, Yujun Cui, Rong GuoAbstract:Background: Rhombomys opimus (great gerbil) is a reservoir of Yersinia pestis in the natural plague foci of Central Asia. Great gerbils are highly resistant to Y. pestis infection. The coevolution of great gerbils and Y. pestis is believed to play an important role in the plague epidemics in Central Asia plague foci. However, the dynamics of Y. pestis infection and the corresponding antibody response in great gerbils have not been evaluated. In this report, animal experiments were employed to investigate the bacterial load in both the liver and spleen of infected great gerbils. The dynamics of the antibody response to the F1 capsule antigen of Y. pestis was also determined. Methodology: Captured great gerbils that tested negative for both anti-F1 antibodies and bacterial isolation were infected subcutaneously with different doses (105 to 1011 CFU) of a Y. pestis strain isolated from a live great gerbil during routine plague surveillance in the Junggar Basin, Xinjiang, China. The clinical manifestations, changes in body weight, anal temperature, and gross anatomy of the infected animals were observed. The blood cell count, bacterial load, and anti-F1 antibody titers were determined at different time points after infection using a blood analyzer, plate counts, and an indirect hemagglutination assay, respectively. Conclusions/Significance: The dynamics of bacterial load and the anti-F1 antibody concentration in great gerbils are highly variable among individuals. The Y. pestis infection in great gerbils could persist as long as 15 days. They act as a
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transmission efficiency of the plague pathogen y pestis by the flea xenopsylla skrjabini to mice and great gerbils
Parasites & Vectors, 2015Co-Authors: Yujiang Zhang, Qiguo Wang, Hongjian Chen, Kemei Wu, Azhati Rehemu, Xiaotao Yu, Ruifu Yang, Xinhui Wang, Weiwei Meng, Yajun SongAbstract:Background Plague, a zoonotic disease caused by Yersinia pestis, is characterized by its ability to persist in the plague natural foci. Junggar Basin plague focus was recently identified in China, with Rhombomys opimus (great gerbils) and Xenopsylla skrjabini as the main reservoir and vector for plague. No transmission efficiency data of X. skrjabini for Y. pestis is available till now.
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Study on the spatial distribution and related risks of Rhombomys opimus, based on the ecological niche modeling in Junggar Basin, Xinjiang
Zhonghua liu xing bing xue za zhi = Zhonghua liuxingbingxue zazhi, 2014Co-Authors: Mei Wang, Qiguo Wang, Tao Luo, Jian Zhao, Ti Azha, Yujiang ZhangAbstract:Objective In order to understand the distribution of the host animals in Junggar Basin,this study intended to map the spatial distribution and identifying the risk of Rhombomys opimus in the framework of ecological niche theory based on the "3S" technology.Methods Data on Rhombomys opimus was obtained through a series of field surveys.Environmental variables were achieved through data from Remote Sensing.Maxent modeling was built to map the potential distribution of Rhombomys opimus,with its risks identified.Results The prediction model showed ideal accuracy,with the AUC value as 0.968.Probability of Maximum Youden Index was defined as the threshold being used.The sensitivity and specificity showed as 91.4％ and 63.3％,respectively.The accuracy was 73.8％,and the Kappa coefficient was 0.495.The positive predictive value was 59.7％.The negative predictive value was 92.6％.The predicted high risk area was 37 304 km2,with 6.2％ in the whole area,distributed in 18 counties,including Changji Hui Autonomous Prefecture,Urumqi,Karamay and so on.The number of people under high risk would come about 120 000,scattering in the areas of 261 square kilometers.Conclusion It was feasible to predict the potential distribution of Rhombomys opimus based on the ecological niche theory as well as environmental variables derived from data through remote sensing.More specific high-risk areas could be identified under this technique so as to guide the monitoring programs. Key words: Plague foci; Ecological niche modeling; Geographical information system
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Dynamics of Yersinia pestis and its antibody response in great gerbils (Rhombomys opimus) by subcutaneous infection.
PloS one, 2012Co-Authors: Yujiang Zhang, Qiguo Wang, Azhati Rehemu, Xinhui Wang, Weiwei Meng, Xiang Dai, Tao Luo, Abulimiti Maituohuti, Yujun Cui, Rong GuoAbstract:Background Rhombomys opimus (great gerbil) is a reservoir of Yersinia pestis in the natural plague foci of Central Asia. Great gerbils are highly resistant to Y. pestis infection. The coevolution of great gerbils and Y. pestis is believed to play an important role in the plague epidemics in Central Asia plague foci. However, the dynamics of Y. pestis infection and the corresponding antibody response in great gerbils have not been evaluated. In this report, animal experiments were employed to investigate the bacterial load in both the liver and spleen of infected great gerbils. The dynamics of the antibody response to the F1 capsule antigen of Y. pestis was also determined. Methodology Captured great gerbils that tested negative for both anti-F1 antibodies and bacterial isolation were infected subcutaneously with different doses (105 to 1011 CFU) of a Y. pestis strain isolated from a live great gerbil during routine plague surveillance in the Junggar Basin, Xinjiang, China. The clinical manifestations, changes in body weight, anal temperature, and gross anatomy of the infected animals were observed. The blood cell count, bacterial load, and anti-F1 antibody titers were determined at different time points after infection using a blood analyzer, plate counts, and an indirect hemagglutination assay, respectively. Conclusions/Significance The dynamics of bacterial load and the anti-F1 antibody concentration in great gerbils are highly variable among individuals. The Y. pestis infection in great gerbils could persist as long as 15 days. They act as an appropriate reservoir for plague in the Junggar Basin, which is part of the natural plague foci in Central Asia. The dynamics of the Y. pestis susceptibility of great gerbil will improve the understanding of its variable resistance, which would facilitate the development of more effective countermeasures for controlling plague epidemics in this focus.
Rong Guo - One of the best experts on this subject based on the ideXlab platform.
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Dynamics of F1 antibody responses to Yersinia pestis infection in Rhombomys opimus
Zhonghua yu fang yi xue za zhi [Chinese journal of preventive medicine], 2017Co-Authors: Weiwei Meng, Qiguo Wang, Xinhui Wang, Tao Luo, Abulikemu, Burenmingde, Azati, Abulimiti, Rong GuoAbstract:Objective: To observe the dynamics of antibody response in great gerbils infected with Yersinia pestis in experiment. Method: A total of 211 great gerbils were captured in the southern margin of plague natural focus of Junggar Basin of the Xinjiang Uygur Autonomous Region in 2011. Among them, there were 167 great gerbils without infection of Y. pestis and 44 great gerbils infected by Y.pestis. Y.pestis No. 2504 was employed for this experimental strain, which was strong toxic strain with negativity in the reduction experiment of nitrate. 35 great gerbils without the infection of Y. pestis were divided randomly and averagely into 7 groups including 6 experimental groups and 1 control group. Great gerbils in the 1st to 6th experimental groups were exposed first with 1 × 10(6)-1 × 10(11) CFU/ml of bacterial fluid with 10 times of gradient dilution; groin areas of great gerbils in the control group were injected subcutaneously with physiological saline; and the amount of infection was all 1 ml. 17 great gerbils infected with Y. pestis and the first detection of F1-antibody titer in 1∶256-1∶4 096 were grouped according to F1-antibody titer: group 1∶4 096 (n=4), group 1∶2 048 (n=4), group 1∶1 024 (n=3), group 1∶512 (n=3) and group 1∶256 (n=3); and blood in caudal regions was collected in asepsis for the detection of F1-antibody, with a total of 5 times. 9 great gerbils which were selected from the remaining great gerbils infected with Y. pestis and detected F1-antibody negative 2 times were exposed 1×10(6) CFU/ml of bacterial fluid for the second infection, with the amount of infection being 1 ml. Blood in caudal regions of great gerbils after the first and second infection were collected for the detection of plague F1-antibody on the 3rd, 5th, 7th, 15th, 30th, 60th, 90th and 120th day after infection. Declined regression models for great gerbils' antibodies were established with unary linear regression equation; declined change diagrams for the antibodies were drawn to observe the declined F1-antibody after great gerbils were exposed to Y. pestis. Results: In great gerbils with the first infection of Y. pestis, antibodies were detected in the 1 × 10(6)-1 × 10(8) CFU/ml of group on the 30th, 15th and 15th day, respectively; the positive rates of antibody were 1/4, 3/4 and 4/5, respectively; the group 1×10(7) and 1× 10(8) CFU/ml reached to the highest antibody titer with 1∶256 on the 120th day; antibodies were revealed in the group 1×10(9), 1×10(10) and 1×10(11) CFU/ml from the 5th to 7th day when the seroconversion of all antibodies was observed; group 1×10(11) CFU/ml reached to the highest antibody titer on the 120th day with 1∶4 096. In the great gerbils with the second exposure to Y.pestis, positive antibodies were detected on the 3rd day with the positive rate being 2/9; and the highest antibody titer with 1∶2 048 was noted on the 90th day. Unary linear regression equation of declined F1 antibody of great gerbils was y=0.045x- 0.321 (F=115.40, P< 0.001), and the shortest duration for F1-antibody titer declining from 1∶4 096 to 0 was 140 d and the longest duration 200 d. Conclusion: Great gerbils infected with the high concentration of Y. pestis fluid show shorter duration in producing F1-antibody, the antibody positive rate is also higher, and the highest antibody titer can reach 1∶4 096. The great gerbils could hold the plague F1 antibodies for a long time which was about 140 to 200 days from the highest titer.
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Dynamics of Yersinia pestis and Its Antibody Response in Great Gerbils (Rhombomys opimus) by Subcutaneous Infection
2016Co-Authors: Yujiang Zhang, Qiguo Wang, Azhati Rehemu, Xinhui Wang, Weiwei Meng, Xiang Dai, Tao Luo, Abulimiti Maituohuti, Yujun Cui, Rong GuoAbstract:Background: Rhombomys opimus (great gerbil) is a reservoir of Yersinia pestis in the natural plague foci of Central Asia. Great gerbils are highly resistant to Y. pestis infection. The coevolution of great gerbils and Y. pestis is believed to play an important role in the plague epidemics in Central Asia plague foci. However, the dynamics of Y. pestis infection and the corresponding antibody response in great gerbils have not been evaluated. In this report, animal experiments were employed to investigate the bacterial load in both the liver and spleen of infected great gerbils. The dynamics of the antibody response to the F1 capsule antigen of Y. pestis was also determined. Methodology: Captured great gerbils that tested negative for both anti-F1 antibodies and bacterial isolation were infected subcutaneously with different doses (105 to 1011 CFU) of a Y. pestis strain isolated from a live great gerbil during routine plague surveillance in the Junggar Basin, Xinjiang, China. The clinical manifestations, changes in body weight, anal temperature, and gross anatomy of the infected animals were observed. The blood cell count, bacterial load, and anti-F1 antibody titers were determined at different time points after infection using a blood analyzer, plate counts, and an indirect hemagglutination assay, respectively. Conclusions/Significance: The dynamics of bacterial load and the anti-F1 antibody concentration in great gerbils are highly variable among individuals. The Y. pestis infection in great gerbils could persist as long as 15 days. They act as a
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Dynamics of Yersinia pestis and its antibody response in great gerbils (Rhombomys opimus) by subcutaneous infection.
PloS one, 2012Co-Authors: Yujiang Zhang, Qiguo Wang, Azhati Rehemu, Xinhui Wang, Weiwei Meng, Xiang Dai, Tao Luo, Abulimiti Maituohuti, Yujun Cui, Rong GuoAbstract:Background Rhombomys opimus (great gerbil) is a reservoir of Yersinia pestis in the natural plague foci of Central Asia. Great gerbils are highly resistant to Y. pestis infection. The coevolution of great gerbils and Y. pestis is believed to play an important role in the plague epidemics in Central Asia plague foci. However, the dynamics of Y. pestis infection and the corresponding antibody response in great gerbils have not been evaluated. In this report, animal experiments were employed to investigate the bacterial load in both the liver and spleen of infected great gerbils. The dynamics of the antibody response to the F1 capsule antigen of Y. pestis was also determined. Methodology Captured great gerbils that tested negative for both anti-F1 antibodies and bacterial isolation were infected subcutaneously with different doses (105 to 1011 CFU) of a Y. pestis strain isolated from a live great gerbil during routine plague surveillance in the Junggar Basin, Xinjiang, China. The clinical manifestations, changes in body weight, anal temperature, and gross anatomy of the infected animals were observed. The blood cell count, bacterial load, and anti-F1 antibody titers were determined at different time points after infection using a blood analyzer, plate counts, and an indirect hemagglutination assay, respectively. Conclusions/Significance The dynamics of bacterial load and the anti-F1 antibody concentration in great gerbils are highly variable among individuals. The Y. pestis infection in great gerbils could persist as long as 15 days. They act as an appropriate reservoir for plague in the Junggar Basin, which is part of the natural plague foci in Central Asia. The dynamics of the Y. pestis susceptibility of great gerbil will improve the understanding of its variable resistance, which would facilitate the development of more effective countermeasures for controlling plague epidemics in this focus.
Parviz Parvizi - One of the best experts on this subject based on the ideXlab platform.
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novel identification of leishmania major in hemiechinus auritus and molecular detection of this parasite in meriones libycus from an important foci of zoonotic cutaneous leishmaniasis in iran
Journal of Infection and Public Health, 2014Co-Authors: Soheila Rouhani, Asad Mirzaei, Adel Spotin, Parviz ParviziAbstract:Summary Background: One of the well-known foci of zoonotic cutaneous leishmaniasis (ZCL) in Iran is Turkemen Sahara, which is located in north eastern Iran. ZCL is a disease of mammals, and humans can become infected as accidental hosts. Many researchers have argued that Rhombomys opimus is the only main reservoir host of ZCL in this region of the Golestan province. No other rodents or mammals are thought to host or have been reported to host Leishmania parasites in this region. This research was designed and developed to isolate, detect and firmly identify Leishmania parasites in mammals and rodents other than R. opimus. Methods: Wild mammals were caught from gerbil burrows. Leishmania parasites were detected to assess the infection of reservoir hosts in 2010. Each genomic DNA sample was screened for Leishmania infection via nested PCR and sequencing using the internal transcribed spacer ribosomal DNA (ITS-rDNA) identification protocol for parasites. Results: The greatest number of infections (8/19) were found in Meriones libycus. One in three infections was found in Hemiechinus auritus, and this is the first report of infection in this species. Only Leishmania major was definitively identified and unambiguously typed in M. libycus and H. auritus. The infection rates in these two wild mammals were not significantly different, and no other gerbil parasites were detected in M. libycus or H. auritus at our study site.
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Phlebotomus papatasi (Scopoli) (Diptera:
2006Co-Authors: Parviz Parvizi, Paul D. Ready, Leishmania Major YakimoffAbstract:Phlebotomus papatasi is an important vector of L. major in Iran. P. papatasi was collected from peridomestic animal shelters, inside and around the houses and also the nearby burrows of the gerbil reservoir hosts, Rhombomys opimus, in several provinces in Iran. Mitochondrial Cytochrome b (Cyt b) of sandflies, which is a maternally-inherited gene marker, was used to see if there is any "isolation by distance " over a large geographical scale among Iranian provinces. The analyses were based on the last 717 bp of the Cyt b gene followed by 20 bp of intergenic spacer and the transfer tRNA ser (TCN) gene, i.e. the 737 bp fragment (without primers) amplified with the primers CB1-SE and CB-R06. Cyt b Long fragment sequences were obtained from 149 out of 177 specimens of P. papatasi and 49 haplotypes were identified. Based on the Cyt b Long fragment examined, P. papatasi showed only recent divergence in Iran, because the genetic distances between haplotypes were small. However, some evidence for isolation by distance was found. First, all the haplotypes from Iran did not belong to a single network, whereas most from Golestan province (Iran) did belong to a single network. Second, there were some abundant haplotypes that were found only in one province. Iran. Biomed. J. 10 (2): 69
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first detection of leishmania major in peridomestic phlebotomus papatasi from isfahan province iran comparison of nested pcr of nuclear its ribosomal dna and semi nested pcr of minicircle kinetoplast dna
Acta Tropica, 2005Co-Authors: Parviz Parvizi, Isabel Mauricio, Ana M Aransay, Michael A Miles, P D ReadyAbstract:Two PCR methods were compared for their sensitivity in detecting cultured Leishmania major, before being used to estimate infection rates in female sandflies (Phlebotomus papatasi) collected from peridomestic animal shelters and the nearby burrows of the gerbil reservoir hosts, Rhombomys opimus, in Isfahan province, central Iran. A semi-nested PCR was used to amplify a fragment of minicircle kinetoplast (k) DNA with a length and sequence diagnostic for L. major, and a nested PCR was developed to amplify a fragment containing the internal transcribed spacers of the ribosomal RNA genes (ITS-rDNA) with a sequence diagnostic for L. major. The semi-nested PCR was less sensitive than the nested PCR when using DNA extracted from cultured promastigotes of L. major, but it was more sensitive for detecting L. major in wild-caught sandflies. At the edges of two Isfahan villages, infection rates were significantly higher in P.papatasi collected outside gerbil burrows (14/28) compared with those from peridomestic animal shelters (2/21). This is the first record of L. major detected in P.papatasi from peridomestic sites in Isfahan province.