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1.
Summary Nerves and ganglia from a variety of fish, amphibian, reptilian and mammalian species were studied by optical and electron microscopy. Observations using the Picrosirius-polarization method strongly suggest that two different types of collagen fibers are present in the connective tissues of nerves and ganglia. Electron microscopy of nerves and ganglia showed the presence of two different collagen fibril populations, distinguishable on the basis of diameter, located in different compartments of these structures. Thicker fibrils are present in nerve and ganglionic epineurium. Thinner fibrils are present in the endoneurium, surrounding nerve fibers and ganglionic cells, and between the concentric layers of perineurial cells. These results were consistently observed in all species studied and very probably represent a general phenomenon in vertebrates.This work was aided by a grant from the Fundação de Amparo à Pesquisa do Estado de São Paulo  相似文献   

2.
Summary Three cases of histoplasmosis are described, one also with subcutaneous nodule, the first cases reported from Pernambuco, Brasil.Histoplasma capsulatum was isolated from tissues in two cases and from sputum in two cases, all in pure culture.Docente Livre de Parasitologia, Chefe de Secção de Micologia. Cat. Prof.Alvaro de Figueiredo.Professor, Washington University, formerly Visiting Professor, Cadeira de Parasitologia.Pesquisadora, Cadeira de Parasitologia, Secção de Micologia.  相似文献   

3.
The partially-purified, thermally-stable trehalase from conidia of Humicola grisea was highly specific for trehalose and was free of potentially interfering activities. The enzyme was fully stable when stored in solution at -15°C for at least 6 months. This preparation could be used to quantify trehalose from 0.05 to 1.25 mol/ml either in carbohydrate mixtures or in complex biological materials.M.J. Neves, H.F. Terenzi and J.A. Jorge are with Departmento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirao Preto, Universidade de São Paulo, 14040-901-Ribeirão Preto, São Paulo, Brazil; F.A. Leone is with Departamento de Quimica, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901-Ribeirão Preto, São Paulo, Brazil.  相似文献   

4.
Feeding experiments with two species of carnivorous copepod, Mesocyclops longisetus (Thiebaud) and Mesocyclops kieferi Van de Velde from Barra Bonita, a eutrophic reservoir in São Paulo, Brasil, were performed using two common types of prey: Ceriodaphnia cornuta, a cladoceran, with a mean body length of 464 µm (including spines) or 393 µm (without spines), and Brachionus calyciflorus, a rotifer with a mean body length of 350 µm (including spines) or 279 µm (without spines).Both species showed higher consumption rates on Brachionus than on Ceriodaphnia. For Mesocyclops longisetus, the average rates were: 2.19 prey ind–1 h–1 (Brachionus), and 1.30 prey ind–1 h–1 (Ceriodaphnia). For Mesocyclops kieferi, the rates were 1.85 prey ind–1 h–1 (Brachionus) and 0.60 prey ind–1 h–1 (Ceriodaphnia). These experimental data are discussed with reference to the dynamics of the predator and prey populations in the reservoir.Laboratorio de Limnologia, Departamento de Ciencias Biologicas, Universidade Federal de São CarlosCentro de Recursos Hidricos e Ecologia Aplicada Lab. de Limnologia, Departamento de Hidraulica e Saneamento, Escola de Engenharia de São Carlos, Universidade de São Paulo  相似文献   

5.
Trichophyton mentagrophytes infection was studied in a breeding colony of 42 white mice. Symptoms were observed in only 3 out of the 12 animals shown to carry dermatophyte on their coats.Literature on Trichophyton mentagrophytes infection in mice is reviewed. The use of the technique developed by Mariat & Tapia (16) to isolate dermatophytes on cultures, specially for epidemiological surveys, is postulated.Attention is called to the importance of healthy animals, directly or indirectly, as carriers of fungi and sources of infection to other animals and human beings.
Resumo E feita uma revisão da literatura sobre infecção, em camundongos, por T. mentagrophytes e descrita uma epizootia em camundongos do biotério da Escola Paulista de Medicina.Dos 42 animais usados para experimentação, 3 apresentavam lesões descamativas na cabeça e dorso. T. mentagrophytes foi isolado, em cultivo, de 2 dos camundongos com lesão e de 10 animais, clinicamente sadios. A tecnica desenvolvida por Mariat & Tapia para isolamento de fungos do tegumento de animais e de pacientes, com ou sem lesões visiveis, em áreas extensas do corpo, parece ser a mais indicada, pela praticabilidade e facilidade de seu uso, principalmente em amplos inquéritos epidemiológicos. Chama-se atenção para a importância dos animais sadios, como vetores de esporos de fungos e fontes de infecção, diretamente ou indirectamente, para o homem e outros animais.
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6.
Summary We present a method to test if the proportion of 45,X cases resulting from loss of the maternal chromosome or of cases of 46,X,i(Xq) with the isochromosome of maternal origin is different from 1/2. The available data are consistent with the hypothesis that the normal X present in i(Xq) patients originates with equal probabilities in the fathers and mothers of the patientsThis paper was supported in part by grants from Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)  相似文献   

7.
The decrease in viscosity is widely used to estimate the activity of pectinolytic enzymes. This method is shown to be influenced by the production strain and this prevents an accurate comparison between the activities of different microorganisms, especially under different conditions.A.E. Maiorano and Y. Ogaki are with the Divisão de Quimica, with the Agrupamento de Biotecnologia, Instituto de Pesquisas Tecnológicas do Estado de São Paulo S/A.-IPT, Cidade Universitária, Caixa Postal 7141, CEP 01064-970, São Paulo, SP, Brazil; W. Schmidell is with the Departamento de Engenharia Quimica, Escola Politécnia, Universidade de São Paulo, Caixa Postal 61548, CEP 05424-970, São Paulo, SP, Brazil.  相似文献   

8.
A heparan sulfate-rich proteoglycan is on the surface of NMuMG mouse mammary epithelial cells apparently intercalated into their plasma membranes. Mild treatment of the cells with trypsin releases the GAG-bearing region (ectodomain) of this molecule as a discrete proteoglycan which is readily purified. At physiological pH and ionic strength, the ectodomain binds collagen types I, III, and V but not types II, IV, or denatured type I. The proteoglycan binds to a single class of high affinity saturable sites on type I collagen fibrils, sites which are selective for heparin-like glycosaminoglycans. The binding of NMuMG cells to type I collagen duplicates that of their cell surface proteoglycan; cells bind to native but not denatured collagen, and binding is inhibited by heparin but not by other glycosaminoglycans. These binding properties suggest that cell surface heparan sulfate proteoglycans could act as receptors for interstitial collagens and mediate changes in cell behavior induced by collagenous matrices.  相似文献   

9.
High activities of extracellular pectinase with viscosity-diminishing and reducing groups-releasing activities were produced by Penicillium frequentans after 48 h at 35°C, in agitated cultures supplemented with 0.5% citrus pectin and initial pH of 2.5. Under these conditions the fungus also produced high activity of pectinesterase. At an initial pH of 7.0 or 8.0, pectin lyase activity was also detected. Enzyme activity releasing reducing sugars was more stable at 50°C than viscosity-diminishing activity. Both activities were maximal at pH 2.5 to 5.2 and at 55°C.The authors are from the Faculdade de Ciências Farmacêuticas de Ribeirão Preto da Universidade de São Paulo, Avenida do Café, s/no, Bairro Monte Alegre, 14.049 Ribeirão Preto, S.P., Brazil.  相似文献   

10.
Summary The authors review and comment on Brazilian literature on the observations of South American Blastomycotic lesion in perineal, anal and/or rectal localization.They relate a case of a patient presenting a perineal lesion two years after the excision of a tumor caused byP. brasiliensis in the brain.They comment onMackinnon's pathogenic theory of South American Blastomycosis that presumes that lungs are the portal of entry ofP. brasiliensis by inhalation of its spores. Thus, mucocutaneous lesions are secondary to a primary pulmonary localization by hematogenous route.
Sumário Os autores revisam e comentam a literatura brasileira sôbre as observacões de Blastomicose Sul-americana com localização peineoano-retal.Relatam a observação de um paciente no qual a lesão perineal surgiu dois anos após a ablação de um tumor do cérebro porP. brasiliensis.Discutem a casuística à luz da teoria patogênica deMackinnon, admitindo que a porta de entrada do fungo seja pelas vias aéreas, por inhalação dos espórios do fungo. As lesões mucocutãneas são pois secundárias à localização pulmonar primária, (às vêzes inaparantes) da qual resultam por disseminaçåo hematógena.
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11.
In order to study isolation within the salians subgroup, pair mating crosses involving its 7 species were performed. The results of testing different interspecific combinations varied from complete isolation at the insemination level to the production of fertile hybrids. Some isolation indices are proposed: Ii (isolation index at the insemination level), Fi (isolation index at the fertilization level), Ti (total isolation index), and Ai (average isolation index). A schema of the biological relationships on the basis of the isolation degree is also presented for the 7 species of the subgroup.Part of this study was included in the thesis submitted for the PH.D. degree at the University of São Paulo and was performed during the tenure of a fellowship supported by the Fundação de Amparo à Pesquisa do Estado de São Paulo.  相似文献   

12.
The fate of exogenous glycosaminoglycans in cultures of strongly (RMS 0) and weakly (RMS 8) metastatic rat rhabdomyosarcoma cells was studied. The time course and concentration dependence of binding and internalization of the radiolabeled sulfated glycosaminoglycans were determined. Weakly metastatic cells took up heparin, heparan and dermatan sulfates into their pericellular compartment at a higher rate than the strongly metastatic RMS 0 cells. The RMS 8 cells exhibited about two times more binding sites for these iduronic acid containing glycosaminoglycans, and internalized higher amounts of them than the RMS 0 cells. The uptake of the chondroitin sulfate into the peri- and intracellular compartments of both cell types was about 5-15% of that of the other glycosaminoglycans studied. The specificity of displacement of the pericellular heparin and dermatan sulfate by the unlabeled glycosaminoglycans indicates the involvement of specific structural features of the polysaccharide chains in the interactions of glycosaminoglycans with the surface of rhabdomyosarcoma cells, beside ionic forces due to the polyanionic character of the glycosaminoglycans. Heparin and heparan sulfate degradation products, mainly large oligosaccharides, were recovered from the surface of RMS 0 cells but were absent on the surface of the RMS 8 cells. About 30% of the internalized heparin and heparan sulfate was present in the partially degraded form in both cell types. Oligosaccharides derived from glycosaminoglycans were not released into the medium. The decrease in the amount of iduronic acid containing glycosaminoglycans internalized by the highly invasive cells seems to be correlated with an increased cell-associated degradation and with an apparent loss of glycosaminoglycan binding sites on the cell surface.  相似文献   

13.
Summary ERG amplitude facilitation, observed in the eye ofAtta sexdens after light adaptation, was studied as a function of duration and intensity of adaptation, of dark interval between adapting and test stimuli, and of level of steady background illumination. Results show that sensitivity facilitation in this eye cannot be regarded as a minor effect since it covers a 2 log unit range, the same as that obtained for conditions that produce sensitivity reduction. Maximum facilitation occurs with short and intense light adaptation. The time span of the effect is close to 2 min, and its maximum amplitude may be attained up to 20 s after light adaptation. Increase in background illumination gradually erases facilitation. However, the facilitated response is less sensitive to background illumination than the dark adapted response. Long durations of light adaptation cause ERG decrease, or inhibition. A comparison of these two end results of light adaptation suggests that they arise from different processes, perhaps with distinct origins.Supported by a grant from Fundação de Amparo à Pesquisa do Estado de São Paulo, to the senior author (Contract n 71/1141)With a Fellowship from Fundação de Amparo à Pesquisa do Estado de São Paulo (N 74/388)We wish to express our appreciation to Henrique Fix for his editorial assistance, and to Celia Jablonka for laboratory help.  相似文献   

14.
Dermal cells isolated from the back of 7-day chick embryos were cultured on homogeneous two-dimensional substrates consisting of one or two extracellular matrix components (type I, III or IV collagen, fibronectin and several glycosaminoglycans: hyaluronate, chondroitin-4, chondroitin-6, dermatan or heparan sulfate). The effect of these substrates on cell behavior was compared with that of culture dish polystyrene. Three parameters of cell behavior were examined: cell proliferation and patterning, spreading (cell surface) and locomotion (velocity and directionality). Data were collected by sequential microphotography and analyzed by computer assisted morphometry. Types I and III collagen, hyaluronate and heparan sulfate had a slowing down effect on cell proliferation and patterning. The inhibitory effect of type I collagen was also detected in mixtures with glycosaminoglycans. The other components had no effect. While the smallest spreading was observed on fibronectin substrate, the largest was recorded on chondroitin-6 sulfate and heparan sulfate. The slowest velocity of locomotion was measured on fibronectin, types I and IV collagen and a mixture of type I collagen and chondroitin-6 sulfate. The fastest speed was recorded on chondroitin-4 sulfate. These effects are discussed in view of our knowledge of the role of the dermis in the development of skin and cutaneous appendages, and in the light of the morphogenetically related microheterogeneous distribution of collagens, fibronectin and various glycosaminoglycans in the developing skin.  相似文献   

15.
A case of paracoccidioidomycosis with ocular involvement is studied. Brazilian literature is reviewed. The scarcity of human ocular mycosis is commented on. The most frequent clinic aspects of ocular lesions in natural mycosis are described.
Resumo Um caso de paracoccidioidomicose pulmonar e linfática seguido de comprometimento conjuntivo-palpebral é estudado, em São Paulo.A literatura nacional é revista. As lesões oculares, mais frequentemente verificadas, na paracoccidioidomicose natural são descritas, minuciosamente. O pequeno número de casos humanos com comprometimento ocular é discutido.A severidade e a frequencia das lesões oculares em animais inoculados intracardiacamente, com cultivos de P. brasiliensis sugerem disseminação hematogênica ocular da paracoccidioidomicose humana.
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16.
Collagen XIV, a fibril-associated collagen with interrupted triple helices, is expressed in differentiated soft connective tissues and in cartilage. However, a cellular receptor for this protein has not been identified. Here we show that human placental collagen XIV, isolated by a mild and simple two-step method, serves as adhesive protein for a variety of mesenchymal and some epithelial cells. Cell adhesion could be inhibited by preincubation of the collagen XIV substrate with heparin or with the chondroitin/dermatan sulfate proteoglycan decorin and by pretreatment of cells with chondroitinase ABC or heparinase III, suggesting a cell membrane proteoglycan as receptor. Affinity chromatography of125I-labeled fibroblast cell surface proteins on collagen XIV–Sepharose yielded a chondroitin/dermatan sulfate proteoglycan with a molecular mass of 97–105 kDa after chondroitinase ABC digestion and of 60–70 kDa after further treatment withN-glycosidase F. The eluates contained also some high-molecular-weight material that was susceptible to digestion with heparinase but no detectable integrins. Immunoprecipitation with a specific monoclonal antibody identified the prominent chondroitin/dermatan sulfate proteoglycan as a member of the CD44 family. The interaction between collagen XIV and cells appears to be finely tuned, since matrix-associated glycosaminoglycans, and particularly proteoglycans like decorin, could compete with cells for the binding site(s) on collagen XIV under physiological conditions.  相似文献   

17.
A freshly-prepared yeast extract at 30 or 50 g/l improved the growth of Bradyrhizobium japonicum SEMIA 587 in a 5-l stirred fermenter. Monosodium glutamate or a commercial yeast extract at 2.0 g/l almost doubled cell mass productivity and cell viability when added at the end of the first exponential growth phase.The authors are with the Divisão de Quimica, Agrupamento de Biotecnologia, Instituto de Pesquisas Tecnológicas do Estado de São Paulo, S/A.-IPT-Cidade Universitária s/n., Caixa Postal 7141, CEP 01064-970, São Paulo, SP, Brazil  相似文献   

18.
Regeneration of corneal tissue   总被引:2,自引:0,他引:2  
Penetrating wounds in rabbit corneas heal to form an opaque tissue that eventually becomes transparent. DNA content, dry weight, water content, and collagen content of the tissue gradually become more like that of normal cornea. The healing tissues also synthesize low-sulfated keratan sulfate, hyaluronic acid, and heparan sulfate. These glycosaminoglycans are not found in normal adult corneas but have been reported in fetal corneas. Previous studies have shown that collagen from healing corneal wounds and collagen from fetal corneas have very similar cross-linking patterns, but these patterns are different from those in normal adult collagen. The similarities between collagen and glycosaminoglycans in healing corneal wounds and in fetuses suggest some recapitulation of ontogenetic processes. The biochemical sequence and eventual return of transparency to the rabbit cornea indicate a capability for true regeneration of stromal tissue in the rabbit.  相似文献   

19.
Summary We deal with a new variety ofAspergillus which we callAspergillus gracilis Bainiervar. sartoryi (Biourge) Batista, Lima and Vital.This variety appears to be very important under the phylogenetic point of view, apparently being an intermediate form betweenAspergillus andPenicillium.Its morphology resemblesA. gracilis but the conidia characteristics are distinct; we took the epithetsartoryi fromA. sartoryi Biourge which was not described by the respective author.We suggest, too, the transfer of the seriesA. restrictus, where we put our new variety, from the groupA. glaucus, to become independant, as a connective series in the phylogenetic development betweenAspergillus andPenicillium, since the type of the series and the other elements that it embraces does not produce sclerotia or cleistothecia and the conidial apparatus offers curious similarity toPenicillium. Besides, some fungi of the series grow well in certain culture media, in complete discordance with the members of the groupA. glaucus.

Publiçacão no 4

Chefe do Instituto de Micologia;

Diretor do Instituto de Antibióticos e Prof. de Microbiologia da Escola de Química;

Assistente micologista do Instituto de Micologia — (Todos da Universidade do Recife).

Os autores declinam o seu agradecimento ao Dr.Heraldo da Silva maia, Assistente micologista eD. Marilene Maranhão Moreira, Auxiliar-Técnico, do Instituto de Micologia, pela colaboração que lhes prestaram, durante a realização do presente trabalho.  相似文献   

20.
There is evidence to suggest that extracellular matrix molecules, such as proteoglycans, are involved in the regulation of mineral deposition in calcifying tissues. One mineralizing system which is characterized by extremely rapid mineralization is the hen eggshell. This eggshell consists of a pair of nonmineralized eggshell membranes subjacent to the calcified eggshell proper; the eggshell proper is organized into palisades (columns) of mineralized matrix separated by pores. Between the membranes and the shell proper are compacted foci of tissue called mammillary knobs, which are thought to be sites where mineralization is initiated. Previous work from this laboratory has shown the presence of types I, V, and X collagen in the shell membranes. To address the question of the possible role of proteoglycans and glycosaminoglycans in mineralization of the eggshell, two approaches were used. First, immunohistochemistry was performed with monoclonal antibodies to various proteoglycan and glycosaminoglycan epitopes. This analysis indicates that different glycosaminoglycans are localized to discrete regions within the eggshell. Dermatan sulfate is present within the matrix of the shell proper and, to a lesser extent, the mammillary knobs and the outer portion of the shell membranes. In contrast, keratan sulfate is found in the shell membranes and prominently in the mammillary knobs. Interestingly, different keratan sulfate antibodies immunostain distinct regions of the eggshell, which suggests that various types of keratan sulfate are distributed differently. The second approach utilized was to extract the eggshell membranes and recover anionic molecules by anion-exchange chromatography. This resulted in the extraction of material which was recognized by antibodies to keratan sulfate, but not to chondroitin sulfate. This material was very large, as evidenced by its elution in the void volume of a Sepharose CL-2B column. The large size may be due to the extensive cross-links known to occur in the eggshell. If eggshell membranes are extracted at elevated temperature, the material recovered is of much smaller size. These results indicate that molecules recognized by antibodies to glycosaminoglycans are present in the eggshell, and their localized distribution relative to the calcified matrix suggests that they may be involved in the regulation of mineral deposition.  相似文献   

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