RESUMEN
Amblyospora weiseri n.sp., parasite of the mosquito Aedes cantans in Czechoslovakia has two sporulation sequences: the octosporous sporulation sequence occurs in oenocytes and fat body tissue of larvae, involves meiosis and results in the formation of eight uninucleate spores (octospores) enclosed in a sporophorous vesicle and is fatal for the host. Octospores are not infectious to other larvae. The oenocytic sequence localized in oenocytes of larvae and adults of both sexes probably effects transovarial transmission to the next mosquito generation and involves the formation of isolated binucleate spores. The oenocytic development differs from the same sequence found in other mosquito Amblyospora, as it involves the development of uninucleate meronts and large plasmodia with single nuclei as well as binucleate stages. A. weiseri n.sp. is another member of the genus Amblyospora in which sporulation is not dependent upon the host taking a blood meal. Preliminary attemps to infect Cyclops strenuus and Megacyclops gigas with octospores failed.
RESUMEN
The ultrastructural cytology of the microsporidium Bacillidium cyclopisVávra, 1962, a parasite of the copepod Acantho cyclop s americanus in Czechoslovakia, is described, with emphasis on the mature spore. All life cycle stages are diplokaryotic. The three-layered spore wall has a stratified exospore. The polaroplast has two distinctly separated lamellar parts where the lamellae are folded concentrically around the anterior part of the polar filament. Anterior lamellae are narrow and closely packed; posterior lamellae are wider and more loosely arranged. The polar filament has an anterior straight and wide section, the "manubrium", where the posterior third is widened in a characteristic manner, and a final section, arranged in 2-3 narrow, isofilar coils. The attachment of the polar filament is more or less oblique in relation to the long axis of the spore. The ejected filament leaves the spore in a distinct angle, and the narrow part is characteristically and regularly coiled. Glycoconjugates are present in the layers of the anchoring disc, in one of the external layers of the manubroid part of the polar filament, and in two distinct layers of the coils. The diplokaryon partially encloses the manubrium in a mantle-like fashion. B. cyclopis is compared to re-examined preparations of Mrazekia argoisiiLéger and Hesse, 1916. These two species are the only Bacillidium-like microsporidia of Crustacea, and they are distinguished from all the other Bacillidium-like microsporidia by their swollen posterior end of the manubrium. This character, which is easily seen also using light microscopy, is considered diagnostic for the genus Mrazekia, and B. cyclopis is transferred to this genus. Mrazekiidae Léger and Hesse, 1922 is the valid family name, with Bacillidiidae Larsson, 1986 as a junior synonym.
RESUMEN
Developmental stages (sporoblasts and spores) of five species of microsporidia (Amblyospora bracteata, A. varians, A. weiseri, Nosema apis, Tuzetia sp.), fixed by conventional EM fixatives or by glutaraldehyde supplemented with potassium chloride, were studied by freeze-fracture using ultrathin sections as controls. It was found that the polar filament is formed by coalescence of cytoplasmic vesicles of the Golgi zone. The filament is enveloped by a single cytoplasmic membrane ("filament ensheathing membrane" = FEM) showing more intramembrane particles (IP) on the EF face (in the order of 1000 IP/µm(2)) and less IP (in the order of 500 IP/µm(2)) on the PF face. During maturation of the spore the IP on the FEM progressively disappear. The polaroplast is a stack of cytoplasmic membranes revealing more IP (in the order of 1500 IP/µm(2)) on the PF face and less particles (in the order of 400 IP/µm(2)) on the EF face. When KCl is added to the fixative the polaroplast remains unswollen and its membranes are smooth. In swollen polaroplasts the membranes are modified, probably by mechanical stretching. The polaroplast membranes are not direct outgrowths of the FEM. The posterior vacuole is limited by a single cytoplasmic membrane. No evidence was found supporting the idea that the filament ends in the posterior vacuole.
RESUMEN
The effects of subinhibitory concentrations of antibiotics on polymorphonuclear leukocyte (PML) and serum killing of Staphylococcus aureus 502A (UC 9116) and Escherichia coli UC 9451 were studied. Exposure of these bacteria to subinhibitory levels of certain lincosaminides, spectinomycin, or 6'-n-propylspectinomycin altered their susceptibility to these host defense mechanisms, while exposure to gentamicin had no effect. However, each organism responded differently to treatment with the antibiotics. S. aureus pretreated during log phase growth with subinhibitory concentrations of clindamycin, lincomycin, or pirlimycin was more susceptible to killing by PMLs than untreated bacteria. No effect on phagocytic killing was found when S. aureus was pretreated with spectinomycin, 6'-n-propylspectinomycin, or gentamicin. The S. aureus remained resistant to serum lysis despite antibiotic treatment. In contrast, spectinomycin and 6'-n-propylspectinomycin as well as clindamycin dramatically increased the susceptibility of E. coli to serum lysis (greater than 99% destroyed). Moderate killing of E. coli by PMLs was also found.
Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Actividad Bactericida de la Sangre , Lincomicina/farmacología , Fagocitosis , Espectinomicina/farmacología , Clindamicina/farmacología , Escherichia coli/efectos de los fármacos , Escherichia coli/inmunología , Humanos , Neutrófilos/inmunología , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/inmunologíaRESUMEN
A microsporidium Nosema portugal n. sp. was isolated from gypsy moths, Lymantria dispar L, collected near Lisbon, Portugal, in 1985. The life cycle includes two sequential developmental cycles, a primary and a secondary cycle. The primary cycle occurs in midgut epithelial cells, where primary spores are produced within 48 h. The primary spores immediately extrude their polar filaments, presumably to infect other cells. In the target tissues (salivary glands and fat body) the secondary development cycle is followed by the formation of environmental spores. Primary spores were also sometimes present in target tissues. Fresh unfixed and unstained primary spores have a large posterior vacuole and measured 4.8 x 2.7 &mgr;m. Ultrastructurally, they have 5-8 polar filament coils, a large posterior vacuole, abundant endoplasmic reticulum, and were binucleate. Mature unfixed and unstained environmental spores were highly refractive and the posterior vacuole and nuclei could not be seen through the spore coat. Fresh environmental spores measured 4.5 x 1.9 &mgr;m. Ultrastructurally, environmental spores were binucleate, with a typical polaroplast, 10-11 isofilar polar filament coils, and a series of 4-6 thin polar filament-like tubules situated at the posterior end of the row of typical polar filament coils. The ssu rRNA sequences strongly suggest that this species is more closely related to the Vairimorpha subgroup within the Nosema/Vairimorpha clade than to the Nosema subgroup. Copyright 1999 Academic Press.
RESUMEN
Serum samples of rabbits, guinea pigs, Syrian golden hamsters and mice from various breeding stations and laboratory colonies were examined for the presence of antibodies to Encephalitozoon cuniculi by the indirect fluorescent antibody test (IFAT). Of more than 500 rabbits, only those from commercial farms and laboratory colonies were found positive. The number of positive animals fluctuated in different colonies from 0% to 95%. 140 guinea pigs were examined. Two colonies were antibody-free, four colonies contained 29-85% of positively reacting animals. 110 Syrian golden hamsters from five colonies showed that in four colonies 14-80% of animals reacted positively and only one colony was negative. Of 126 rats examined, 15% and 30% of animals from two colonies contained significant antibody levels. Two colonies were negative. 200 mice from a number of colonies did not show any significant positivity. The significance of these results is discussed.
Asunto(s)
Animales de Laboratorio/parasitología , Anticuerpos/análisis , Apicomplexa/inmunología , Animales , Animales de Laboratorio/inmunología , Cricetinae , Técnica del Anticuerpo Fluorescente , Cobayas , Mesocricetus , RatonesRESUMEN
In 43 animals, representing 36% of a sample of 117 domestic rabbits, antibodies to Sarcocystis were detected using indirect immunofluorescent antibody test (IFAT). Experimental transmission of the parasite from rabbit to cat and back to rabbit proved that the organism involved was Sarcocystis cuniculi Brumpt, 1913. The antibody response in experimental transmission was revealed by IFAT: the level of antibodies was generally low and the antibodies disappeared in less than 100 days p.i., while the parasites still remained viable in host's muscle tissue. The diagnosis of rabbit sarcosporidiosis in the definitive and intermediate hosts is discussed.
Asunto(s)
Conejos/parasitología , Sarcocystis/crecimiento & desarrollo , Sarcocistosis/veterinaria , Animales , Formación de Anticuerpos , Enfermedades de los Gatos/transmisión , Gatos , Sarcocystis/inmunología , Sarcocistosis/parasitología , Sarcocistosis/transmisiónRESUMEN
A new microsporidian species Amblyospora indicola sp. n., parasite of fat body cells of Culex sitiens larvae, is described. Separation of diplokaryon nuclei occurs during the early sporulation phase of this microsporidian followed by the appearance of synaptonemal complexes in the nuclei suggesting that the first sporogonial division is meiotic.
Asunto(s)
Apicomplexa/patogenicidad , Culex/parasitología , Animales , Apicomplexa/ultraestructura , Culex/ultraestructura , Larva , Microscopía Electrónica , Especificidad de la EspecieRESUMEN
Conditions for the effective fluorescence labelling of microsporidian spores by optical brighteners, based on the presence of chitin in the spore wall, are described. Spores of Vairimorpha ephestiae, V. necatrix, V. plodiae, Nosema bombycis, N. apis, N. algerae, Encephalitozoon cuniculi and Enterocytozoon bieneusi were examined. The degree of binding of Calcofluor White M2R (CFW) to untreated spores depends on the conditions and time of storage and the degree of bacterial contamination of the spore sample. Unpurified spores, stored in water are unreliable as control material for the estimation of CFW labelling. However, spores subjected to alkaline treatment by NaOH before CFW application are visualized with ease under all experimental conditions by their bright, not quenching fluorescence in shortwave light (approximately 350 nm) in CFW dilutions of 10(-4) or even lower. Similar improvement in labelling is achieved by exposing spores to CFW dissolved in 0.5-1N NaOH. As well as Calcofluor White M2R other optical brighteners (e.g. Uvitex 2B, Ciba-Geigy or Rylux BA, Ostacolor) can be used for labelling of spores.
Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/parasitología , Microsporida/citología , Microsporidiosis/diagnóstico , Coloración y Etiquetado/métodos , Animales , Humanos , Microscopía Fluorescente , Esporas/citologíaRESUMEN
Sections of corneal tissue infected with Microsporidium ceylonensis were restained or processed for electron microscopy. Confirmation was obtained that the parasite develops in macrophages and that spores are uninucleate. New information is provided that sporoblasts and spores develop synchronously within a membrane in the host cell, spores have an anisofilar polar tube of 6-10 wide coils and 2-3 narrow coils and details are given of the spore wall and internal organisation. The parasite was compared on the one hand with Encephalitozoon, which exhibits asynchronous intravacuolar development of merogonic and sporogonic stages and has spores with isofilar polar tubes and on the other hand with species reported from mammals, of which the sporogonic stages develop synchronously within sporophorous vesicles and the spores have anisofilar polar tubes. Even so, a generic emplacement could not be established. Attention is drawn to the similarities between M. ceylonensis and Nosema sp. described from the cornea of a woman in Botswana.
Asunto(s)
Córnea/parasitología , Infecciones Parasitarias del Ojo/parasitología , Queratitis/parasitología , Microsporida/ultraestructura , Microsporidiosis/parasitología , Animales , Niño , Córnea/patología , Trasplante de Córnea , Femenino , Humanos , Macrófagos/parasitología , Masculino , Microscopía Electrónica , Esporas/ultraestructuraRESUMEN
The authors deal with the surgical technique of the reconstruction of coxa vara in children. They present valgus osteotomy on the Pauwels principle with the simultaneous apophyseodesis of the growth plate of greater trochanter, lengthening of fermoral neck fixed by 120 degrees angled blade plate for adolescents allowing a parallel lengthening of the lower limb. The main indication for this technique is postdysplastic coxa vara and congenital coxa vara in children. However, it may be used also in adults. The benefits of the method consist in the possibility of exact planning of the surgery. Key words: valgus osteotomy, reconstruction, DDH, ischemic necrosis of the femoral head.
RESUMEN
The authors present long-term results of the surgical treatment of ischemic necrosis of proximal femur resulting from the treatment of the developmental dysplasia. They used their own technique of intertrochanteric valgus osteotomy in 77 hip joints. The surgical technique was published in the first part of the work. It consists in valgus osteotomy which lengthens femoral neck and, consequently also the whole limb. At the same time a fusion of the physis of the greater trochanter was performed and the pathological antetorsion of the femoral neck corrected. Osteotomy was fixed with a special valgus angled blade plate. In cases where dysplastic acetabulum persists the authors supplement the operation with the shelf operation after Bosworth. All patients operated on for the ischemic necrosis of femoral head were originally treated conservatively. Of the operated on group of 77 hip joints, 69 hip joints were classified in type III after Bucholz-Ogden and 8 hip joints in type II (type II B after Thomas et al.). Valgus operation was performed in children at the age of 3 to 15 years. The patients were further followed up on average 15,4 years, the average age upon the termination of the follow-up was 24,7 years. Eight patients of the group underwent a revision surgery by the same technique for inadequate primary correction or for the loss of correction in the course of the further growth of the hip joint. In 4 patients the authors equalized the length of both limbs by shortening the contralateral femur, in 3 patients additional fusion of the physis of the greater trochanter was performed. In case of dysplastic acetabulum the shelf arthroplasty after Bosworth proved to be very suitable. On the basis of their experience and clinical results the authors recommend to perform the surgery at the age between 7 and 10 years as in earlier operations there may occur a loss of correction during the following period and in children operated on later the adaptation of the operated on hip joint decreases. A prerequisite of a good long-term result is a precise preoperative planning of the operation and its exact technical performance. Key words: developmental dysplasia of the hip joint, ischemic necrosis, valgus intertrochanteric osteotomy of femur.
RESUMEN
The work presents the evaluation of longterm results of the surgical prolongation of the femur. The examined group includes 10 patients: 5 boys and 5 girls which the authors treated in the years 1978-1986. Their average age in time of operation was 15.5 years. The youngest was 8 and the oldest 25 years old. Shortening was in 4 cases caused by poor healing of the fracture, in three cases it was a results of congenital hypoplasia of the femur or the whole lower extremity, in three cases it was caused by osteomyelitis. The duration of the prolongation was on average 4 months, the external fixation device was removed on average after 8 months. The mean prolongation was 8 cm, ranging from 4 cm to 11 cm. In 8 cases healing was without complications, twice there occurred a fatigue fracture which was treated by plate osteosynthesis.
Asunto(s)
Alargamiento Óseo/instrumentación , Fémur/cirugía , Adolescente , Adulto , Alargamiento Óseo/métodos , Niño , Femenino , Fémur/diagnóstico por imagen , Humanos , Masculino , Dispositivos de Fijación Ortopédica , RadiografíaRESUMEN
In order to analyze the relationship between VO2 max and height, body mass and lean body mass a multi-longitudinal survey was conducted on three different age groups of randomly selected children from a small Czech community. Beginning at the initial ages of 8, 12 and 16 years subjects were subsequently retested three times at two year intervals. At overlapping ages there were no differences in the various age groups between height and VO2 max. By utilizing mean values for the various parameters at specific calendar ages a growth curve was constructed for each sex for the age range 8 to 20 years. The values were compared with longitudinal studies of various countries and no substantial differences were found. When VO2 max was then compared to height, body mass and lean body mass it was apparent that the almost linear relationship with height was the most precise. In addition the children remained, generally speaking, in their same rank order for VO2 max for the three different age groupings.