Investigation of the intimate relationship between the human malaria parasite Plasmodium falciparum and its Anopheles vector requires the reliable production and isolation of successive sexual stages of the parasite f...Investigation of the intimate relationship between the human malaria parasite Plasmodium falciparum and its Anopheles vector requires the reliable production and isolation of successive sexual stages of the parasite from infected mosquitoes. Such an advance in propagation would benefit a range of molecular, cellular, immunochemical and transmission-blocking research studies. Parasite cultivation, mosquito rearing, infection and subsequent dissection of mosquitoes are all highly technical procedures that require both skill and experience to perform with competence. Furthermore, to produce mosquitoes of an appropriate age to infect during the short period in which parasites are viable for infection demands precise planning in order to coordinate the interacting life cycles of the parasite and vector. Here, a protocol is described for the complete development of P. falciparum within Anopheles stephensi. A very consistent, high level production in vivo of P. falciparum oocysts and sporozoites is demonstrable by dissection of the mosquito midgut and salivary glands, respectively.展开更多
Anopheles stephenst, infected with Plasinodium yoelii, was fed with 10% sucrose solution contatning 1% difluoromethylornithine (DFMO) to induce oocyst degeneration of the malaria parasites. On the 11th day after infec...Anopheles stephenst, infected with Plasinodium yoelii, was fed with 10% sucrose solution contatning 1% difluoromethylornithine (DFMO) to induce oocyst degeneration of the malaria parasites. On the 11th day after infection, the effects of mosquito hemocytes On the normal and degenerated oocysts were observed under transmission electron microscope. In the control group, no hemocyte could be found around the normally-developed oocysts. In the DFMO-treated group, all the oocysts underwent degeneration in various degrees and some of them were melanized. All the oocysts were attached by one or more hemocytes of the kind of granulocytes.There were many granules with microtubular structure in the cytoplasm of the hemocytes and in the space between the hemocyte and the oocyst. The findings suggest that the degeneration of oocysts can attract the hemocytes to attach around them and the latter can release granules and possibly other substances to cause encapsulation and melanization of the oocvsts.展开更多
Contamination of soil with cryptosporidial oocysts poses a great health risk to people especially in individuals who are immune-compromised. Exposure to contaminated soil can cause diarrhoea in humans especially in ch...Contamination of soil with cryptosporidial oocysts poses a great health risk to people especially in individuals who are immune-compromised. Exposure to contaminated soil can cause diarrhoea in humans especially in children who play around the parks and may not wash their hands before handling food. The prevalence of cryptosporidial oocyst in soils of 4 recreational parks in Abuja, Nigeria was investigated. Four hundred soil samples were collected from various locations within the recreational parks and examined for the presence of cryptosporidial oocyst using modified acid fast staining technique. In nine (2.3%) of the samples, 8 were from park A and 1 was from park B contained cryptosporidial oocyst. There was significant association (χ2 = 20.1;df = 2;p = 0.00004) between prevalence of Cryptosporidium oocysts and level of hygiene of the parks. It was concluded that soil in recreational parks may be a source of infection with Cryptosporidium oocysts.展开更多
To optimize the production process of occidium vaccine and provide the basis and methods for the production of live vaccine,this experiment uses the collected liquid with different centrifugal forces and centrifugatio...To optimize the production process of occidium vaccine and provide the basis and methods for the production of live vaccine,this experiment uses the collected liquid with different centrifugal forces and centrifugation time,to measure and compare the recovery,purity,collection time and costs of coccidian oocyst,for the purpose of exploring the impact of washing conditions on coccidian oocyst collection in chicken manure.The results show that for the centrifugal machine with the radius of 17.2 cm,the best washing centrifugal rotational speed is 2500 rpm /min,that is,the best washing centrifugal force RCF = 1201.85 g,and the centrifugation time is 12 min.展开更多
Objective: To determine the occurrence of Cryptosporidium oocysts in edible frogs (Rana spp.) sold at the Hanwa frog market, Zaria, Kaduna State, Nigeria. Methods: A total of 117 frogs (Rana spp.) were randomly collec...Objective: To determine the occurrence of Cryptosporidium oocysts in edible frogs (Rana spp.) sold at the Hanwa frog market, Zaria, Kaduna State, Nigeria. Methods: A total of 117 frogs (Rana spp.) were randomly collected based on consent and availability at the market. The intestinal contents from the frogs were examined by staining flotation and sedimentation smears with modified Ziehl-Neelsen staining technique and microscopy of the oocysts. Results: Overall, 35.9% of frogs sampled from the Hanwa frog market were positive for Cryptosporidium oocysts. There were more Cryptosporidium oocysts detected by sedimentation test (28.2%) than flotation test (23.9%). There was no significant statistical association between sex of frogs and oocyst detection (χ2 = 0.5349, P > 0.05). Also, there was no correlation between the weights of frogs and the sizes of the Cryptosporidium oocysts detected (r = 0.0109, P > 0.05). Nevertheless, female frogs (40%) and frogs within the weight range 170–219 g were more infected with Cryptosporidium (66.7%). Oocysts size range 6.10–7.00 μm had the highest frequency of 10 (23.8%). By size 28.2% of the oocysts detected suggested infection with Cryptosporidium parvum and Cryptosporidium maleagridis. Conclusions: This study has established that edible frogs (Rana spp.) sold at the Hanwa frog market for human consumption were infected with Cryptosporidium spp. which constitutes a valid public health risk especially for immunocompromised individuals.展开更多
为了筛选有效的球虫消毒剂,本研究将柔嫩艾美耳球虫卵囊分别与16种常用消毒剂和1种高效抗球虫药物溶液(250mg/L妥曲珠利溶液)混合作用2h然后在2.5%重铬酸钾溶液中孢子化培养,或混合作用4h后接种14日龄雏鸡,根据卵囊孢子化率、孢子化抑...为了筛选有效的球虫消毒剂,本研究将柔嫩艾美耳球虫卵囊分别与16种常用消毒剂和1种高效抗球虫药物溶液(250mg/L妥曲珠利溶液)混合作用2h然后在2.5%重铬酸钾溶液中孢子化培养,或混合作用4h后接种14日龄雏鸡,根据卵囊孢子化率、孢子化抑制率、每克粪便卵囊数量(oocysts per gram of feces,OPG)、病变计分和血便情况评价消毒剂和抗球虫药物抑杀球虫卵囊效果。结果显示,8%氨水对未孢子化卵囊和孢子化卵囊均表现为100%的抑杀效果;250mg/L妥曲珠利、3%甲醛、4%苯酚、0.5%过氧乙酸、5%NaOH+10%NaCl和5%NaOH对球虫卵囊活性具有一定的抑制作用,孢子化抑制率超过10%,但是对孢子化卵囊抑杀作用不明显;而剩余10种常用消毒剂对球虫卵囊没有明显的抑杀作用。氨水抑杀球虫卵囊条件优化的试验结果显示,1%～8%氨水与未孢子化卵囊作用1h以上,均可100%抑杀球虫卵囊活性。粪便干扰试验结果显示,粪便不影响2%和4%氨水对球虫卵囊的抑杀效果。本研究结果说明常用消毒剂和抗球虫药物不能有效杀灭球虫卵囊的活性,而氨水是一种高效球虫消毒剂。本研究结果可为开发新型高效球虫消毒剂和球虫病控制提供参考。展开更多
文摘Investigation of the intimate relationship between the human malaria parasite Plasmodium falciparum and its Anopheles vector requires the reliable production and isolation of successive sexual stages of the parasite from infected mosquitoes. Such an advance in propagation would benefit a range of molecular, cellular, immunochemical and transmission-blocking research studies. Parasite cultivation, mosquito rearing, infection and subsequent dissection of mosquitoes are all highly technical procedures that require both skill and experience to perform with competence. Furthermore, to produce mosquitoes of an appropriate age to infect during the short period in which parasites are viable for infection demands precise planning in order to coordinate the interacting life cycles of the parasite and vector. Here, a protocol is described for the complete development of P. falciparum within Anopheles stephensi. A very consistent, high level production in vivo of P. falciparum oocysts and sporozoites is demonstrable by dissection of the mosquito midgut and salivary glands, respectively.
文摘Anopheles stephenst, infected with Plasinodium yoelii, was fed with 10% sucrose solution contatning 1% difluoromethylornithine (DFMO) to induce oocyst degeneration of the malaria parasites. On the 11th day after infection, the effects of mosquito hemocytes On the normal and degenerated oocysts were observed under transmission electron microscope. In the control group, no hemocyte could be found around the normally-developed oocysts. In the DFMO-treated group, all the oocysts underwent degeneration in various degrees and some of them were melanized. All the oocysts were attached by one or more hemocytes of the kind of granulocytes.There were many granules with microtubular structure in the cytoplasm of the hemocytes and in the space between the hemocyte and the oocyst. The findings suggest that the degeneration of oocysts can attract the hemocytes to attach around them and the latter can release granules and possibly other substances to cause encapsulation and melanization of the oocvsts.
文摘Contamination of soil with cryptosporidial oocysts poses a great health risk to people especially in individuals who are immune-compromised. Exposure to contaminated soil can cause diarrhoea in humans especially in children who play around the parks and may not wash their hands before handling food. The prevalence of cryptosporidial oocyst in soils of 4 recreational parks in Abuja, Nigeria was investigated. Four hundred soil samples were collected from various locations within the recreational parks and examined for the presence of cryptosporidial oocyst using modified acid fast staining technique. In nine (2.3%) of the samples, 8 were from park A and 1 was from park B contained cryptosporidial oocyst. There was significant association (χ2 = 20.1;df = 2;p = 0.00004) between prevalence of Cryptosporidium oocysts and level of hygiene of the parks. It was concluded that soil in recreational parks may be a source of infection with Cryptosporidium oocysts.
文摘To optimize the production process of occidium vaccine and provide the basis and methods for the production of live vaccine,this experiment uses the collected liquid with different centrifugal forces and centrifugation time,to measure and compare the recovery,purity,collection time and costs of coccidian oocyst,for the purpose of exploring the impact of washing conditions on coccidian oocyst collection in chicken manure.The results show that for the centrifugal machine with the radius of 17.2 cm,the best washing centrifugal rotational speed is 2500 rpm /min,that is,the best washing centrifugal force RCF = 1201.85 g,and the centrifugation time is 12 min.
文摘Objective: To determine the occurrence of Cryptosporidium oocysts in edible frogs (Rana spp.) sold at the Hanwa frog market, Zaria, Kaduna State, Nigeria. Methods: A total of 117 frogs (Rana spp.) were randomly collected based on consent and availability at the market. The intestinal contents from the frogs were examined by staining flotation and sedimentation smears with modified Ziehl-Neelsen staining technique and microscopy of the oocysts. Results: Overall, 35.9% of frogs sampled from the Hanwa frog market were positive for Cryptosporidium oocysts. There were more Cryptosporidium oocysts detected by sedimentation test (28.2%) than flotation test (23.9%). There was no significant statistical association between sex of frogs and oocyst detection (χ2 = 0.5349, P > 0.05). Also, there was no correlation between the weights of frogs and the sizes of the Cryptosporidium oocysts detected (r = 0.0109, P > 0.05). Nevertheless, female frogs (40%) and frogs within the weight range 170–219 g were more infected with Cryptosporidium (66.7%). Oocysts size range 6.10–7.00 μm had the highest frequency of 10 (23.8%). By size 28.2% of the oocysts detected suggested infection with Cryptosporidium parvum and Cryptosporidium maleagridis. Conclusions: This study has established that edible frogs (Rana spp.) sold at the Hanwa frog market for human consumption were infected with Cryptosporidium spp. which constitutes a valid public health risk especially for immunocompromised individuals.
文摘为了筛选有效的球虫消毒剂,本研究将柔嫩艾美耳球虫卵囊分别与16种常用消毒剂和1种高效抗球虫药物溶液(250mg/L妥曲珠利溶液)混合作用2h然后在2.5%重铬酸钾溶液中孢子化培养,或混合作用4h后接种14日龄雏鸡,根据卵囊孢子化率、孢子化抑制率、每克粪便卵囊数量(oocysts per gram of feces,OPG)、病变计分和血便情况评价消毒剂和抗球虫药物抑杀球虫卵囊效果。结果显示,8%氨水对未孢子化卵囊和孢子化卵囊均表现为100%的抑杀效果;250mg/L妥曲珠利、3%甲醛、4%苯酚、0.5%过氧乙酸、5%NaOH+10%NaCl和5%NaOH对球虫卵囊活性具有一定的抑制作用,孢子化抑制率超过10%,但是对孢子化卵囊抑杀作用不明显;而剩余10种常用消毒剂对球虫卵囊没有明显的抑杀作用。氨水抑杀球虫卵囊条件优化的试验结果显示,1%～8%氨水与未孢子化卵囊作用1h以上,均可100%抑杀球虫卵囊活性。粪便干扰试验结果显示,粪便不影响2%和4%氨水对球虫卵囊的抑杀效果。本研究结果说明常用消毒剂和抗球虫药物不能有效杀灭球虫卵囊的活性,而氨水是一种高效球虫消毒剂。本研究结果可为开发新型高效球虫消毒剂和球虫病控制提供参考。
