Direct xenodiagnosis has been used to determine the infection rates in sand flies of 12 dogs para... more Direct xenodiagnosis has been used to determine the infection rates in sand flies of 12 dogs parasitized by Leishmaniainfantum and classified in function of clinical signs. The dogs were divided into three clinical groups and no statistically significant differences in the infection rates of female sand flies were observed among them. This result indicates the epidemiological importance of asymptomatic and oligosymptomatic dogs. Indirect xenodiagnosis uses sand flies fed on the blood of dogs ex vivo. This technique was not found to be useful as an alternative to the direct method for the detection of dogs parasitized by L.infantum. The clinical worsening of the disease was not reflected in the increasing number of parasites detected in the animals’ blood by the indirect technique, thereby rejecting its utility as an indicator of the prognosis of the disease.
AbstractLeishmania (Leishmania) infantum is the causative agent of both the cutaneous and viscera... more AbstractLeishmania (Leishmania) infantum is the causative agent of both the cutaneous and visceral forms of leishmaniasis in southwest Europe; the dog is the main reservoir. In order to identify the L. (L.) infantum zymodemes present in Spain, a total number of 85 Leishmania stocks isolated from dogs (31), HIV-positive patients (46) with visceral or cutaneous leishmaniasis, a patient with visceral leishmaniasis complicating renal transplantation (1) and immunocompetent patients (7) with visceral or cutaneous leishmaniasis, have been characterized by isoenzyme typing. All canine stocks were MON-1, which is the most widespread zymodeme in the Mediterranean area. In immunocompetent patients three zymodemes were found: MON-1 (2), MON-24 (2) and MON-34 (3). Nine different zymodemes were obtained in stocks from HTV co-infected patients, indicating a higher variability of L. (L.) infantum amongst them: MON-1 (in 21 stocks), MON-24 (7), MON-28 (1), MON-29 (3), MON-33 (7), MON-34 (1) and MON-183 (4). Two new zymodemes, MON-198 (1) and MON-199 (1), were described among HIV patients from Spain. The stock from the renal transplanted patient was MON-1. The exclusive presence of certain zymodemes in immunocompromised patients and their absence in typical cases of cutaneous and visceral
The control of arthropod vectors of pathogens that affect human and animal health is important fo... more The control of arthropod vectors of pathogens that affect human and animal health is important for the eradication of vector-borne diseases. The ortholog of the tick-protective antigen, subolesin, was identified in Aedes albopictus and found to have conserved epitopes in ticks and mosquitoes. RNA interference with the tick and mosquito double-stranded RNA in three tick species resulted in significant gene knockdown and decreased tick weight and/or survival. Feeding Anopheles atroparvus, Aedes caspius, and Culex pipiens female mosquitoes on an A. albopictus subolesin hyperimmune serum resulted in 11 ± 5% to 29 ± 6% survival inhibition when compared to controls fed on preimmune serum. Feeding sand flies, Phlebotomus perniciosus, on antimosquito subolesin ortholog protein antibodies inhibited female survival and the number of larvae and adults obtained after hatching by 28 ± 22% and 16 ± 3%, respectively, when compared to controls. Vaccination with tick and mosquito subolesin ortholog proteins significantly reduced Ixodes scapularis tick infestation and weight in a similar way. However, vaccination with the recombinant mosquito subolesin ortholog antigen did not protect against Amblyomma americanum and Rhipicephalus sanguineus tick infestations. Collectively, these preliminary results provided the first evidence that development of vaccines may be possible for control of multiple arthropod vectors using subolesin orthologs but suggested that multiple antigens may be required to produce an effective vaccine.
Leishmania (Leishmania) infantum is the causative agent of both the cutaneous and visceral forms ... more Leishmania (Leishmania) infantum is the causative agent of both the cutaneous and visceral forms of leishmaniasis in southwest Europe; the dog is the main reservoir. In order to identify the L. (L.) infantum zymodemes present in Spain, a total number of 85 Leishmania stocks isolated from dogs (31), HIV-positive patients (46) with visceral or cutaneous leishmaniasis, a patient with visceral leishmaniasis complicating renal transplantation (1) and immunocompetent patients (7) with visceral or cutaneous leishmaniasis, have been characterized by isoenzyme typing. All canine stocks were MON-1, which is the most widespread zymodeme in the Mediterranean area. In immunocompetent patients three zymodemes were found: MON-1 (2), MON-24 (2) and MON-34 (3). Nine different zymodemes were obtained in stocks from HTV co-infected patients, indicating a higher variability of L. (L.) infantum amongst them: MON-1 (in 21 stocks), MON-24 (7), MON-28 (1), MON-29 (3), MON-33 (7), MON-34 (1) and MON-183 (4). Two new zymodemes, MON-198 (1) and MON-199 (1), were described among HIV patients from Spain. The stock from the renal transplanted patient was MON-1. The exclusive presence of certain zymodemes in immunocompromised patients and their absence in typical cases of cutaneous and visceral
Canine leishmaniasis is caused by Leishmania infantum (syn. L. chagasi, in America) and is transm... more Canine leishmaniasis is caused by Leishmania infantum (syn. L. chagasi, in America) and is transmitted by the bite of phlebotomine sand flies. Infected dogs constitute the main domestic reservoir of the parasite and play a key role in transmission to humans, in which the parasite produces visceral leishmaniasis. The increasing awareness that control of the human disease depends on effective control of canine leishmaniasis has promoted, in the last few years, research into leishmanial infection in dogs. Newly available specific reagents and molecular tools have been applied to the detailed investigation of canine leishmaniasis and important advances have been made in elucidating the epidemiology and pathology of the disease. These new findings have led to better understanding of the disease, and have also helped in the development of new diagnostic methods and control measures against the infection, such as insecticide-impregnated collars for dogs, new drugs and treatment protocols, and second generation vaccines, with the hope of not only reducing the heavy burden of the disease among dogs but also reducing the incidence of human visceral leishmaniasis.
Direct xenodiagnosis has been used to determine the infection rates in sand flies of 12 dogs para... more Direct xenodiagnosis has been used to determine the infection rates in sand flies of 12 dogs parasitized by Leishmaniainfantum and classified in function of clinical signs. The dogs were divided into three clinical groups and no statistically significant differences in the infection rates of female sand flies were observed among them. This result indicates the epidemiological importance of asymptomatic and oligosymptomatic dogs. Indirect xenodiagnosis uses sand flies fed on the blood of dogs ex vivo. This technique was not found to be useful as an alternative to the direct method for the detection of dogs parasitized by L.infantum. The clinical worsening of the disease was not reflected in the increasing number of parasites detected in the animals’ blood by the indirect technique, thereby rejecting its utility as an indicator of the prognosis of the disease.
AbstractLeishmania (Leishmania) infantum is the causative agent of both the cutaneous and viscera... more AbstractLeishmania (Leishmania) infantum is the causative agent of both the cutaneous and visceral forms of leishmaniasis in southwest Europe; the dog is the main reservoir. In order to identify the L. (L.) infantum zymodemes present in Spain, a total number of 85 Leishmania stocks isolated from dogs (31), HIV-positive patients (46) with visceral or cutaneous leishmaniasis, a patient with visceral leishmaniasis complicating renal transplantation (1) and immunocompetent patients (7) with visceral or cutaneous leishmaniasis, have been characterized by isoenzyme typing. All canine stocks were MON-1, which is the most widespread zymodeme in the Mediterranean area. In immunocompetent patients three zymodemes were found: MON-1 (2), MON-24 (2) and MON-34 (3). Nine different zymodemes were obtained in stocks from HTV co-infected patients, indicating a higher variability of L. (L.) infantum amongst them: MON-1 (in 21 stocks), MON-24 (7), MON-28 (1), MON-29 (3), MON-33 (7), MON-34 (1) and MON-183 (4). Two new zymodemes, MON-198 (1) and MON-199 (1), were described among HIV patients from Spain. The stock from the renal transplanted patient was MON-1. The exclusive presence of certain zymodemes in immunocompromised patients and their absence in typical cases of cutaneous and visceral
The control of arthropod vectors of pathogens that affect human and animal health is important fo... more The control of arthropod vectors of pathogens that affect human and animal health is important for the eradication of vector-borne diseases. The ortholog of the tick-protective antigen, subolesin, was identified in Aedes albopictus and found to have conserved epitopes in ticks and mosquitoes. RNA interference with the tick and mosquito double-stranded RNA in three tick species resulted in significant gene knockdown and decreased tick weight and/or survival. Feeding Anopheles atroparvus, Aedes caspius, and Culex pipiens female mosquitoes on an A. albopictus subolesin hyperimmune serum resulted in 11 ± 5% to 29 ± 6% survival inhibition when compared to controls fed on preimmune serum. Feeding sand flies, Phlebotomus perniciosus, on antimosquito subolesin ortholog protein antibodies inhibited female survival and the number of larvae and adults obtained after hatching by 28 ± 22% and 16 ± 3%, respectively, when compared to controls. Vaccination with tick and mosquito subolesin ortholog proteins significantly reduced Ixodes scapularis tick infestation and weight in a similar way. However, vaccination with the recombinant mosquito subolesin ortholog antigen did not protect against Amblyomma americanum and Rhipicephalus sanguineus tick infestations. Collectively, these preliminary results provided the first evidence that development of vaccines may be possible for control of multiple arthropod vectors using subolesin orthologs but suggested that multiple antigens may be required to produce an effective vaccine.
Leishmania (Leishmania) infantum is the causative agent of both the cutaneous and visceral forms ... more Leishmania (Leishmania) infantum is the causative agent of both the cutaneous and visceral forms of leishmaniasis in southwest Europe; the dog is the main reservoir. In order to identify the L. (L.) infantum zymodemes present in Spain, a total number of 85 Leishmania stocks isolated from dogs (31), HIV-positive patients (46) with visceral or cutaneous leishmaniasis, a patient with visceral leishmaniasis complicating renal transplantation (1) and immunocompetent patients (7) with visceral or cutaneous leishmaniasis, have been characterized by isoenzyme typing. All canine stocks were MON-1, which is the most widespread zymodeme in the Mediterranean area. In immunocompetent patients three zymodemes were found: MON-1 (2), MON-24 (2) and MON-34 (3). Nine different zymodemes were obtained in stocks from HTV co-infected patients, indicating a higher variability of L. (L.) infantum amongst them: MON-1 (in 21 stocks), MON-24 (7), MON-28 (1), MON-29 (3), MON-33 (7), MON-34 (1) and MON-183 (4). Two new zymodemes, MON-198 (1) and MON-199 (1), were described among HIV patients from Spain. The stock from the renal transplanted patient was MON-1. The exclusive presence of certain zymodemes in immunocompromised patients and their absence in typical cases of cutaneous and visceral
Canine leishmaniasis is caused by Leishmania infantum (syn. L. chagasi, in America) and is transm... more Canine leishmaniasis is caused by Leishmania infantum (syn. L. chagasi, in America) and is transmitted by the bite of phlebotomine sand flies. Infected dogs constitute the main domestic reservoir of the parasite and play a key role in transmission to humans, in which the parasite produces visceral leishmaniasis. The increasing awareness that control of the human disease depends on effective control of canine leishmaniasis has promoted, in the last few years, research into leishmanial infection in dogs. Newly available specific reagents and molecular tools have been applied to the detailed investigation of canine leishmaniasis and important advances have been made in elucidating the epidemiology and pathology of the disease. These new findings have led to better understanding of the disease, and have also helped in the development of new diagnostic methods and control measures against the infection, such as insecticide-impregnated collars for dogs, new drugs and treatment protocols, and second generation vaccines, with the hope of not only reducing the heavy burden of the disease among dogs but also reducing the incidence of human visceral leishmaniasis.
Uploads
Papers by Ricardo Molina