[A new development in lyophilization: cryodesiccation of nonaqueous systems].
Explore the source record for details and available documents.
Ammonia↗
Biomedical subjects
L Rey
Publications and source records attributed to L Rey.
Ascaris lumbricoides in neonate: evidence of congenital transmission of intestinal nematodes.
Clinical and epidemiological study of a forty-days-old infant with a diarrheic condition and insufficient development led to the coprological diagnosis of ascariasis and possible congenital infection. Specific treatment with levamisole, resulted in clinical and parasitological cure, in addition to gain of weight up to normal levels. Maternal parasitism had been diagnosed two months before labor and proved beyond doubt during the ensuing epidemiological inquiry.
Ascariasis↗
Lethality of triatomines (Hemiptera: Reduviidae), vectors of Chagas' disease, feeding on blood baits containing synthetic insecticides, under laboratory conditions.
A laboratory study was conducted to test the toxicity of synthetic insecticides added to defibrinated sheep blood kept at room temperature and offered as food to the following triatomine species: Triatoma infestans, Panstrongylus megistus, Triatoma vitticeps, Triatoma pseudomaculata, Triatoma brasiliensis and Rhodnius prolixus. The insecticides used, at a concentration of 1 g/l, were: HCH, DDT, Malathion and Trichlorfon, and the lethalithy observed at the end of a 7-day period varied according to the active principle of each. HCH was the most effective by the oral route, killing 100% of the insects, except P. megistus (95.7%) and T. pseudomaculata (94.1%). Trichlorfon killed the insects at rates ranging from 71.8% (T. vitticeps) to 98% (R. prolixus). Malathion was slightly less efficient, killing the insects at rates from 56.8% (T. vitticeps) to 97% (T. brasiliensis). DDT was the least effective, with a killing rate of 10% (T. vitticeps) to 75% (T. brasiliensis). Since the tests were performed at room temperature, we suggest that baits of this type should be tried for the control of triatomines in the field.
Animals↗
Lethal effect of a bait for Rhodnius prolixus (Hemiptera: Reduviidae), the vector of Chagas' disease, containing hexachlorocyclohexane (HCH), under laboratory conditions.
The lethal effect of a bait containing an aqueous hexachlorocyclohexane (HCH) suspension at the concentration of 1g/l and maintained at room temperature was studied in the laboratory over a period of 12 weeks. The suspension was placed in a latex bag hanging inside a 1000-ml beaker tightly covered with nylon netting, and left there with no changes for 85 days. Sixteen groups of R. prolixus bugs, consisting on average of 30 specimens each, were successively exposed to the bait and observed at different intervals for one week each. The mortality rate was 100% for all groups, except for the 16th, whose mortality rate was 96.7%. As the groups succeeded one another, mortality started to occur more rapidly and was more marked at the 6- and 24-h intervals. Later tests respectively started at 6:00 a.m. and 6:00 p.m. showed that diurnal and nocturnal periodicity in the offer of food had no effect on mortality. First- and 2nd- instar nymphs and adults male were more sensitive and 5th- instar nymphs were more resistant to the active principle of the bait.
Animals↗
Comparative study on the localization of adult Schistosoma mansoni worms in albino mice anesthetized with pentobarbital sodium, ether or chloroform.
The effect of anesthetic drugs on the localization of adult worms in albino mice was compared. The animals with 56 days of infection were anesthetized with pentobarbital sodium, ether or chloroform. Perfusion was carried out immediately after, recovering the worms and classifying them in relation to their localization on the liver or portal vein and the mesenteric veins. Our results showed that pentobarbital sodium produced a greater displacement of the worms to the liver (89%) than ether (76%) and chloroform (34%) did, when compared to the control group (22%). The difference between pentobarbital sodium and ether was significant (p < 0.05). We suggest that anesthetic drugs may not be used in studies on the distribution of adult worms in several hosts.
Animals↗
Evaluation of the resistance to Schistosoma mansoni infection in Nectomys squamipes (Rodentia: Cricetidae), a natural host of infection in Brazil.
The development of resistance in three stages throughout an active infection (pre-ovular, acute and initial chronic stages) was studied, comparing the total number of adult worms recovered from the reinfected group and the control groups. It was shown that Nectomys squamipes was unable to develop resistance in the tested conditions and, on the other hand, reinfection in the pre-ovular period of the parasite led the rodent to present the phenomenonacilitation, with reduction of natural resistance and an increase in the parasite load. These results suggest the existence of other forms of immunity diverse from the concomitant immunity in the host-parasite relationship, according to the employed model.
Animals↗
Human pulmonary dirofilariasis: a review.
The authors presented a detailed summary of the geographical distribution, clinical and pathological aspects of human pulmonary dirofilariasis. Although benign, this zoonosis, of which Dirofilaria immitis is the major etiological agent, represents a medical problem since it produces symptoms which may be confused with neoplasia and thus may subject patients to unnecessary thoracic surgery. Of 229 cases cited in the literature, only 17 were reported in Brazil, despite the existence of highly favorable conditions for the transmission of this infection in man. Thus it may well be that this parasitic infection remains underdiagnosed. Finally, the importance of a differential diagnosis between dirofilariasis and pulmonary neoplasia is emphasized in cases where there is a solitary subpleural nodule ("coin lesion") present. In addition, the development and improvement of modern immunological diagnostic techniques are essential to distinguish this benign disease from other pathological conditions and thus avoid unnecessary surgery. These techniques may reveal the true prevalence of this parasitic infection in our environment.
Animals↗
Frequency and precocity of human intestinal parasitism in a group of infants from Rio de Janeiro, Brazil.
Explore the source record for details and available documents.
Animals↗
[Maternal and child intestinal parasitism and breast-feeding].
From March to May 1991, the prevalence of intestinal parasites was detected in 208 children under two-year old, from out patients attending the Public Health Service in Rio de Janeiro. Maternal parasitic infection was simultaneously investigated. Information regarding nurseling's breast-feeding and enteroparasites rates was also recorded. The centrifugal-sedimentation was the method used for stool analysis. Positivity was observed in 12.7% for children and 37.3% for women. Ascaris lumbricoides was the most frequently detected parasite in children under one-year old (4.3%) and mothers (12.7%). The distribution of parasites accordingly to breast-feeding showed a significant statistical difference (p < 0.05) among infants. No exclusively suckled child presented infection. Children whose mothers were infected showed almost two fold risk of infection (1.7). A correlation between enteroparasites and weaned children was observed (r = 0.75). We believe that infected mothers can contribute for parasitic infection of their kids.
Adult↗
[One century of experience with the control of ancylostomiasis].
In the beginning of the XX century, ancylostomiasis was considered a serious public health problem and governments started the first systematic planning for the control of an endemic disease, in large scale. Thereafter, ancylostomiasis was considered a less important subject, because efficient anti-helminthic drugs were introduced, this in combination with the economic development in rich countries, reduced undernourishment and improved housing and sanitary conditions. Consequently, the residual cases of the infection became in general asymptomatic. However, in the third world the problem is still present, and must be considered with realism and managed accordingly. Various suggestions for controling the disease are presented in this paper.
Ancylostomiasis↗
Host-induced morphological changes of Schistosoma mansoni Sambon, 1907 male worms.
In order to evaluate the permissiveness of Nectomys squamipes to Schistosoma mansoni and the influence of the albino mice on the morphological aspects of adult worms derived from a population isolated from N. squamipes, the morphology of adult S. mansoni Sambon, 1907 male worms was studied using a digital image analyser (MOP VIDEOPLAN) and light microscopy. Their sources were as follows: (1) recovered from the wild rodent N. squamipes Brants naturally infected from Sumidouro, RJ, Brazil; (2) recovered from albino mice experimentally infected with the strain derived from N. squamipes; (3) recovered after the isolation of a strain derived from aboriginal human infections in Sumidouro. Worms recovered from N. squamipes (group 1) showed body length and distance between suckers significantly bigger than those of the specimens maintained in mice (groups 2 and 3). The number of testes in group 1 was statistically less than that of groups 2 and 3. Group 2 strains which were maintained in mice, presented the length of the worms as the only significant different character. Data show that: (1) N. squamipes is a more suitable host for the development of S. mansoni when compared to the albino mice; (2) a strain of S. mansoni isolated from a natural host undergoes morphological changes after its passage in the white mouse.
Animals↗
Schistosomiasis in a low prevalence area: incomplete urbanization increasing risk of infection in Paracambi, RJ, Brazil.
The risk of schistosomiasis infection and heavy infection in the locality of Sabugo was evaluated in relation to housing in areas with different urbanization development and to residential supply with snail-infested water. Critical sanitary conditions were found in areas of incomplete urbanization, where healthy water supply sources were scarce, and draining of sewage, without previous treatment, was made directly to the water-bodies used for domestic and leisure activities, despite being Biomphalaria tenagophila snail breeding-places. Stool examinations (Kato-Katz and Lutz methods) showed prevalence of 2.9% mean intensity of 79 eggs per gram of stool and 47% of positive cases presenting intense infection. The use of snail-contaminated water for domestic purposes was considered a risk factor for infection. It is concluded that incomplete urbanization would facilitate transmission, probably enhancing the intensity of infection and that a low prevalence could hide a highly focal transmission. The relevance of these facts upon the efficiency of epidemiologic study methods and disease control planning are then discussed.
Animals↗
[Wild rodents as experimental models of schistosomiasis mansoni: Akodon arviculoides (Rodentia: Cricetidae)].
The experimental infection of A. arviculoides through different routes of penetration of Schistosoma mansoni cercariae (Transcutaneous and subcutaneous) was studied by the kinetics of egg elimination in stools, by the recovery and localization of adult worms (in the portal system and the mesenteric veins) and through the quantitative egg count. It was shown that A. arviculoides infection is similar to the albino mice which served as control in relation to the efficiency of penetration routes, to the adult worms habitat and the egg count. These results suggest that other aspects of the host-parasite relationship should be evaluate so that A. arviculoides may be indicated as an alternative experimental model in schistosomiasis studies.
Animals↗
[Problems posed by benign lymphoid infiltrations of the stomach. Apropos of a gastric lymphoma associated with a lymphoma of the jejunum].
Explore the source record for details and available documents.
Aged↗
Bone cysticercosis caused by Cysticercus racemosus.
Explore the source record for details and available documents.
Aged↗
[Study on breast feeding in a suburban area].
Human milk is considered the best nourishment a child can have during his first months of life, providing that it exists in sufficient amount. In a study of the feeding characteristics in suburban areas of Mexico City, it was found that 71 mothers would continue to breast-feed their children up to the twelfth month. Supplemental feeding began during the first four months with: fruit, vegetables, eggs, meat and in final stages, soups and cereals. The great majority of the mothers thought that human milk is the ideal food for their babies. The medical concept about breast-feeding in the suburban areas of Mexico City is mistaken, due to information based on foreign studies contrary to national reality. In spite of the widespread belief that breast-feeding has decreased in frequency, in this study it was found that it is still popular and commonplace. We recommend that through all information sources, the inestimable value of human milk as an ideal nourishment, due to its nutritional, economical, psychological and hygienic properties, should be emphasized.
Age Factors↗