Changes in motor behavior during pregnancy in rats: the basis for a possible animal model of restless legs syndrome

PURPOSE:Pregnant women have a 2-3 fold higher probability of developing restless legs syndrome (RLS – sleep-related movement disorders) than general population. This study aims to evaluate the behavior and locomotion of rats during pregnancy in order to verify if part of these animals exhibit some RLS-like features.METHODS:We used 14 female 80-day-old Wistar rats that weighed between 200 and 250 g. The rats were distributed into control (CTRL) and pregnant (PN) groups. After a baseline evaluation of their behavior and locomotor activity in an open-field environment, the PN group was inducted into pregnancy, and their behavior and locomotor activity were evaluated on days 3, 10 and 19 of pregnancy and in the post-lactation period in parallel with the CTRL group. The serum iron and transferrin levels in the CTRL and PN groups were analyzed in blood collected after euthanasia by decapitation.RESULTS:There were no significant differences in the total ambulation, grooming events, fecal boli or urine pools between the CTRL and PN groups. However, the PN group exhibited fewer rearing events, increased grooming time and reduced immobilization time than the CTRL group (ANOVA, p<0.05).CONCLUSION:These results suggest that pregnant rats show behavioral and locomotor alterations similar to those observed in animal models of RLS, demonstrating to be a possible animal model of this sleep disorder.

A new model for the immobilization of the rat hind limb

An alternative device for the immobilization of the hind limb of the rat was developed to study the effects of chronic disuse on the soleus and tibialis anterior muscles, maintained for 3 weeks in the shortening and the stretching positions, respectively. The proposed device is made of steel mesh and cotton materials, and has some advantages when compared to cast or plaster cast: it is cheaper, lighter (12 g or 4% of the body weight of the rat) and the same unit can be easily adjusted and used several times in the same animal or in animals of similar size. Immobilization is also useful to restrain the movements of the hip, knee, and ankle joints. Male rats (291 ± 35 g and aged 14 ± 2 weeks) were used to develop and test the model. The soleus muscle of 18 rats was maintained in a shortened position for 21 consecutive days and lost 19 ± 7% of its length (P = 0.008) and 44 ± 6% of its weight (P = 0.002) compared to the contralateral intact muscle. No difference (P = 0.67) was found in the stretched tibialis anterior of the same hind limb when compared to the contralateral muscle. No ulcer, sore or foot swelling was observed in the animals. Immobilization was effective in producing chronic muscle disuse in the hind limbs of rats and is an acceptable alternative to the traditional methods of immobilization such as cast or plaster cast.

Rat hindlimb joint immobilization with acrylic resin orthoses

The objective of the present study was to propose an orthosis of light material that would be functional for the animal and that would maintain only the ankle joint immobilized. Male Wistar rats (3 to 4 months old, 250-300 g) were divided into 2 groups (N = 6): control and immobilized for 7 days. Rats were anesthetized with sodium pentobarbital (40 mg/kg weight) and the left hindlimb was immobilized with the orthoses composed of acrylic resin model, abdominal belt and lateral supports. The following analyses were performed: glycogen content of the soleus, extensor digitorum longus, white gastrocnemius, red gastrocnemius, and tibialis anterior muscles by the phenol sulfuric method, and the weight, fiber area and intramuscular connective tissue of the soleus by the planimetric system. Data were analyzed statistically by the Kolmogorov-Smirnov, Student t and Wilcoxon tests. Immobilization decreased glycogen in all muscles (P < 0.05; soleus: 31.6%, white gastrocnemius: 56.6%, red gastrocnemius: 39%, extensor digitorum longus: 41.7%, tibialis anterior: 45.2%) in addition to reducing soleus weight by 34% (P < 0.05). Furthermore, immobilization promoted reduction of the fiber area (43%, P < 0.05) and increased the connective tissue (200%, P < 0.05). The orthosis model was efficient comparing with another alternative immobilization model, like plaster casts, in promoting skeletal muscle alterations, indicating that it could be used as a new model in other studies related to muscle disuse.

A adequação do consumo de alimentos de origem animal e sua relação com renda familiar

Foi realizado estudo sobre adequação de consumo de proteínas de alto valor biológico e seu relacionamento com preço e com renda familiar, em diferentes épocas. A diminuição de consumo de origem animal observada, foi causada, por uma modificação na distribuição orçamentária, na qual, a fração destinada à aquisição de carne, leite e ovos, em 1975, foi menor do que em 1969. O ''índice de Consumo de Proteínas de Origem Animal - ICPA", avaliado através da razão entre renda familiar e custo dos alimentos de origem animal recomendados para a família, é indicador eficiente do consumo desses alimentos e indiretamente do estado nutricional. Para sua utilização é necessária a fixação de um ICPA crítico, que permita identificar as famílias quanto à capacidade econômica, uma vez que a fração destinada a compra de alimentos de origem animal varia no decorrer do tempo.

Study on the growth promoting capacity of calf and fetal bovine serum for animal cells "in vitro" II: electrophoretic study and survey on the antiproteolytic activity of pools of calf and fetal bovine serum

Calf serum and fetal bovine serum present great variability as to its growth promoting efficiency (GPE). As supplement of culture media to cultivate cells of animal origin they stimulate the "in vitro" multiplication and maintain cell viability. When fourteen lots of calf sera of variable GPE had the total protein contents as well as the percentages of serum fractions determined, no significant differences that could possibly explain the variability of the GPE were observed. Evaluation of the antiproteolytic activity of nineteen lots of calf serum and eighteen serum lots of younger calves showed that the former exhibited lower antiproteolytic titers (1:40 to 1:80) than the latter (1:80 to 1:160). Twelve lots of fetal bovine serum studied in parallel, showed the highest concentration of antiproteolytic factors, with titers equal to 1:320. Sera of bovine origin, but not fetal sera, are usually heat-inactivated, what was demonstrated to be responsible for the decrease of the antiproteolytic activity of 75% of the lots tested. This could explain the inability of certain heat-inactivated sera in promoting multiplication of some cells "in vitro", as verified with primary monkey kidney cells. The results obtained in this study indicated the convenience of submiting each lot of serum to be introduced in cell culture to previous determination of its characteristics, such as growth promoting efficiency, antiproteolytic activity and also toxicity, absence of extraneous agents, etc., in order to minimize the possibility of using serum lots of questionable quality, thus preventing not only the loss of cell lines, but also undesirable and sometimes expensive delays.

Species and biotype distribution of thermotolerant Campylobacters in animal reservoirs in Southern Chile

The prevalence of thermotolerant Campylobacters in mammals and birds from Southern Chile was determined. Campylobacters were isolated from 46.3% of the animals studied being C. jejuni biotipe 1 the most frequent (25.7%) followed by C. coli (17.4%) and C. jejuni biotipe 2 (3.2%).

Febre purpúrica brasileira, virulência em modelo animal do Haemophilus Aegyptius (H. influenzae biogrupo aegyptius)

Febre Purpúrica Brasileira (FPB) é causada por cepas invasoras de Haemophilus aegyptius (H. influenzae biogrupo aegyptius, Hae). Estas cepas invasoras foram diferenciadas de cepas de Hae associadas apenas a conjuntivites (cepas não invasoras) através de marcadores moleculares específicos. Modelo de ratos recém nascidos depletados de complemento foi aplicado ao estudo de cepas de Hae, associadas e não associadas a FPB, com o objetivo de se caracterizar seus potenciais de virulência. Com dose infectante de 10(5) células, as cepas invasoras causaram bacteriemia em 80-100% dos ratos inoculados,.e a magnitude da bacteriemia variou de 10(2,5±0,49) a > 10(4,69) ufc/ml de sangue. Usando a mesma dose infectante as cepas controles não causaram bacteriemia frequente (0 a 50%) e a magnitude variou de 0 a 10(3,69±0,53) ufc/ml de sangue. As doses infectantes capazes de causar bacteriemia em 50% dos ratos inoculados (DB50%) para as cepas invasoras de Hae variaram de < 10³ a 10(4,2) bactérias, enquanto que para as cepas não invasoras, as DB50% variaram de 10(6,2) a > 10(7,3) bactérias. Imunização passiva com antissoros produzidos com cepas invasoras demonstrou que os ratos foram protegidos das bacteriemias causadas pelas cepas homólogas, mas não da infecção causada pela cepa heteróloga. Comparando a bacteriemia causada pelas cepas de Hae com a bacteriemia causada pelo H. influenzae b, cepa Eagan (Hib), foi demonstrado o maior potencial de invasibilidade de Hib. Este modelo animal demonstrou ser útil para esclarecer o maior potencial de virulência das cepas invasoras de Hae.

Paracoccidioides brasilienses isolates obtained from patients with acute and chronic disease exhibit morphological differences after animal passage

The basis for virulence in Paracoccidioides brasiliensis is not completely understood. There is a consensus that the sequencial in vitro subcultivation of P. brasiliensis leads to loss of its pathogenicity, which can be reverted by reisolation from animal passage. Attention to morphological and biochemical properties that are regained or demonstrated after animal passage may provide new insights into factors related to the pathogenicity and virulence of P. brasiliensis. We evaluated morphological characters: the percentage of budding cells, number of buds by cell and the diameter of 100 mother cells of yeast-like cells of 30 P. brasiliensis isolates, before and after animal passage. The isolates were obtained from patients with different clinical forms of paracoccidioidomycosis (PCM): acute form (group A, n=15) and chronic form (group C, n=15). The measurement of the yeast cell sizes was carried out with the aid of an Olympus CBB microscope coupled with a micrometer disc. We measured the major transverse and longitudinal axes of 100 viable cells of each preparation. The percentage of budding cells as also the number of buds by cell was not influenced by animal passage, regardless of the source of the strain (acute or chronic groups). The size values of P. brasiliensis isolates from groups A and C, measured before the animal passage exhibited the same behavior. After animal passage, there was a statistically significant difference between the cell sizes of P. brasiliensis isolates recovered from testicles inoculated with strains from groups A and C. The maximum diameter of mother cells from group A isolates exhibited a size of 42.1mm in contrast with 32.9mm exhibited by mother cells from group C (p<0.05). The diameter of 1500 mother cells from group A isolates exhibited a medium size of 16.0mm (SD ± 4.0), a value significantly higher than the 14.1mm (SD = ± 3.3) exhibited by 1500 mother cells from group C isolates (p<0.05). Our results reinforce the polymorphism exhibited by P. brasiliensis in biological material and the need for further investigations to elucidate the role of morphological parameters of the fungus in the natural history of the disease.

An evaluation of manual and mechanical methods to identify Candida spp. from human and animal sources

To compare two yeast identification methods, i. e, the manual and the VITEK mechanical methods, 62 clinical samples from hemocultures and animal sources were analyzed. After identification as Candida yeasts by the VITEK method, the strains were recharacterized using manual assimilation methods and sugar fermentation tests. Our findings reveal 58% concurrent identification between the two methods for animal strains, and 51% for human hemoculture strains.

Animal helminths in human archaeological remains: a review of zoonoses in the past

The authors present a review of records of intestinal parasitic helminths from animals in human archaeological remains, reported since the emergence of paleopathological studies. The objective was to relate paleoparasitological findings to geographic, biotic, and abiotic factors from the environment in which the prehistoric populations lived, and understand some aspects related to the process of human dispersion and biological and cultural evolution. Modification of eating habits and the incorporation of new cultural practices are analyzed from the perspective of zoonoses from prehistory to the present day, especially in Brazilian indigenous populations. Three tables identifying the helminths, their natural hosts, dates, and sites of archaeological findings complete this review. In conclusion, various zoonoses known today have occurred since antiquity, and these data, combined with studies on the emergence and reemergence of diseases, could make possible to compose scenarios for the future.

ANIMAL MODELS FOR THE STUDY OF LEISHMANIASIS IMMUNOLOGY

Leishmaniasis remains a major public health problem worldwide and is classified as Category I by the TDR/WHO, mainly due to the absence of control. Many experimental models like rodents, dogs and monkeys have been developed, each with specific features, in order to characterize the immune response to Leishmania species, but none reproduces the pathology observed in human disease. Conflicting data may arise in part because different parasite strains or species are being examined, different tissue targets (mice footpad, ear, or base of tail) are being infected, and different numbers (“low” 1×102 and “high” 1×106) of metacyclic promastigotes have been inoculated. Recently, new approaches have been proposed to provide more meaningful data regarding the host response and pathogenesis that parallels human disease. The use of sand fly saliva and low numbers of parasites in experimental infections has led to mimic natural transmission and find new molecules and immune mechanisms which should be considered when designing vaccines and control strategies. Moreover, the use of wild rodents as experimental models has been proposed as a good alternative for studying the host-pathogen relationships and for testing candidate vaccines. To date, using natural reservoirs to study Leishmania infection has been challenging because immunologic reagents for use in wild rodents are lacking. This review discusses the principal immunological findings against Leishmania infection in different animal models highlighting the importance of using experimental conditions similar to natural transmission and reservoir species as experimental models to study the immunopathology of the disease.

The avirulence of the cultivated PF strain of Trypanosoma cruzi: V - the evaluation of parasitologic tests after vaccination of different animal species

After vaccination with the live PF strain of Trypanosoma cruzi, 194 blood cultures were performed in 143 mice, 9 dogs, 5 Cebus monkeys and 7 human subjects. Some of these blood cultures were simultaneously done with xenodiagnosis, subinoculation in baby mice and/or culture of viscerae. The trypanosomes isolated from the few positive cases (6,1%) were incapable of infecting baby mice were considered as cases of immunotolerance. All the other tests were negative.

Salmonelose humana e animal em Araraquara, S. Paulo: prevalência de Shigella em casos humanos

Admitida uma baixa freqüência de Salmonella com base em verificações anteriores em casos de diarréia aguda na cidade de Araraquara, S. Paulo, realizou-se uma investigação com um esquema ampliado para o isolamento de Salmonella a partir de 47 casos de gastroenterite infantil, 51 amostras de fezes de animais e 50 amostras de carnes e vísceras de animais destinados a alimentação. Foram isoladas Salmonella em 6,3% dos casos de gastroenterite, 5,8% de fezes de animais e 8,0% de amostras de alimentos, nesse último caso verificando-se a contaminação exclusivamente em fígado de porco, senão negativos todos os resultados de carne e vísceras de bovinos. Os sorotipos isolados corresponderam, em ordem decrescente de freqüência a S. anatum, S. derby e S. daytona. Nas gastroenterites infantis a freqüência de Shigella (12,7%) foi duas vezes superior à de Salmonella (6,3%).