160 resultados para yellow cardinal


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Last October 2nd the Author smeared nine tubes of Loewenstein medium with material obtained from closed pustulae of a seven years old boy, L2 case of leprosy. This material was very rich in Hansen bacilli in its different forms, inclusive globus, as is seen in the figures 2 and 3 of Plate 1. Part of this material obtained from pustulae opened by galvanocautery, was inoculated, at the same day, into white rats and guinea-pigs. November 26th a new biopsy gave more rich material, which was smeared again into Loewenstein fresh medium. December 15th three of the first and two of the second series of tubes of cultures showed germination of a yellow, dry and rough culture, covering almost the total surface of the medium. Microscopic examination of the culture showed that it was a pure culture of an acid-fast organism. Passages into glycerinated potatoes germinated well covering the surface of the same with a clear yellow granulated culture remaining the fluid (glycerinated water) quite limpid. The germination in glycerinated broth produced a yellow velum in the surface of the medium, as is seen in fig. 3 of Plate 2, without becoming turbid. The microorganism isolated twice from the same source of material was cocciforme (as Mycobacterium pulviforme of Marchoux), in the original culture, becoming more bacilliforme, always acid-fast, after passage into glycerinated media. The A. sent his culture to foreigner colleagues to study it and will inoculate it soon into laboratory animals.

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The outbreak of the jungle or forest yellow fever, through the adapta¬tion, quite recently of the yellow fever virus o the forest mosquitoes, brou¬ght the necessity of ecological researches on hese mosquitoes, as well as on the wild animals they bite, some of them being susceptible to the desease. This has been done by the special yellow fever Service of the State of Sao Paulo, in a special Biological Station in Perús, São Paulo, which has been built in the midst of the jungle. This station was made with plain materials, and covered with straw, but was confortable enough for the technical work, i nthe early months of 1938. During the months in which the investigations were being carried on, the following interesting results were obtained: 1. As we have already pointed out in other places, the forest mosquitoes biting us during daytime, are always new born insects, having not yet sucked blood, as it is the general rule with all mosquitoes, and therefore also, with the anopheles and stegomyia, and this explains why nobody gets malaria or yellow fever, transmitted by anofeles or by aedes aegypti during the day. We think therefore, the jungle yellow fever, got during daytime is not due to the infected jungle or forest mosquito biting, but to infection through the human skin coming into close contact with tre virus, which the forest mosquitoes lay with their dejections, on the leaves of the trees where they remain sitting du¬ring the day. 2. As it is the rule with anopheles, stegomyia and other mosquitoes, the insects once having sucked blood, take nocturnal habits and, therefore, bite us, only during the night, so it happens with the forest mosquito, and insects with developped eggs and blood in stomach have been caught within the sta¬tion house, during the night. During the day, these mosquitoes do not bite, but remain quite still on the leaves of the trees, in the damp parts of the woods. 3. Jungle or forest mosquitoes can easely bite wild animals, some with more avidity then ethers, as it has bee npointed out to the opossum (didei-phis) and other animals. They also bite birds having very thin skin and only exceptionally, cold bloods animals. 5. Is has hot been possible to ascertain how forest mosquitoes are able to live, from onde season to another, through winter, when temperature drops near and even below zero. They have not been found in holes of the terrain, of trees and of animals, as it is the rule in cold countries. During winter, in the forest, it is possible to find larvs in the holes of bambus and trees full of water. As wild animals do not harbour the yellow fever virus for a long time in their body, it is diffcult to explain how the desease lasts from one season to another. Many ecological features on the mosquito, remains yet to be explained and therefore it in necessary to go on with the investigations, in bio¬logical stations, such as that one built up in Perús, São Paulo.

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Fidena callipyga n. sp. is described from three specimens, in the collections of the INSTITUTO OSWALDO CRUZ. It is related to Fidena ornata kröb., 1931 and Fidena aureopygia Kröb., 1931. It can be distinguished from both by the postfrons which is comparatively broader in relation to the high, by the light golden-yellow color of the beard, in striking contrast to the hairs on the propleurae and anterior coxae, and by the extent of the golden-yellow on the abdomen. In size, ornamentation and principally in the form of the palpi it is nearer to aureopygia. Fidena callipyga n. sp. and Melpia miniatistola (End.), 1925 constitute a pair of convergent forms, they differ however not only as to hairs on the mesonotum, femora and hind tibiae and form of the abdomen, but also as to the color of the beard.

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Fidena adnaticornis n. sp. is described from female specimens. It closely resembles Fidena besckii (WIED. ), 1828 and indeed more closely Fidena soledadei (LUTZ), 1911. It can be distinguished from both by the antenna which are so close together that the distance between their basis is less that the width of the first antennal segment; also by the prevalence of yellow hairs on the coxae. In F. soledadei and chiefly in F. besckii the antennae an evidently more separated; they have also few yellow hairs limited to the base extremity of the coxae with prevalence of brown or black hairs. In F. besck the prealar hairs are predominantly yellow ones and there exist yellow hair around the edge of the scutellum, which does not occours in F. adnaticorn and in F. soledadei. In the abdomen the following areas, covered by whit hairs are more extensive in F. besckii: the mid row of white patches on the sternites is more conspicuous and involves the fifth segment; on the sternites instead of stripes the hairs form bands somewhat broader at the middle the respective segment, they may even form triangles with the base as with as the whole segment. Both cotypes of F. soledadei have the hairs damages but, at least, in the 1+2 sternites the areas covered by the white hairs see to be larger than in F. adnaticornis; they have also a higher frons: index : = 2.9.

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The work reported here was carried-out on the invitation of Dr. Henry Kumm, Director of the Rockefeller Foundation, and by appointment from Dr. Henrique Aragão, Director of the Instituto Oswaldo Cruz. It was done during the investigation of sylvan yellow fever, in June 1947, with a view to establishing the phyto-ecological conditions of the county of Passos. The pe¬riod was, however, too short for definite conclusions to be reached. Thanks are due to Dr. O. R. Causey, Chief of Research on Yellow Fever for transpor¬tation and other help. THE REGIONAL VEGETATION. Aerial photographs of the county of Passos shoto that it is covered by three great types of vegetation: Rain Forest, Secondary Pasture Land and Scrub.1 Detailed investigation, however, brings out the fact that these correspond to different seres; furthermore, each type presents not only the specific, characteristics of the biological form dominant for the climate, but also are at various stages, which express HABITATS differing from those of the normal sere. The phytogeographic survey of the region shows that most of it is now covered by secondary pasture land (disclimax) in which Melinis minutiflora, v. "fat grass" (fig. 1), predominates. The mosaic of Rain Forest and of small patches of Scrub reveals the effects of human intervention (BARRETO, H. L. de Mello 1); consequently, all the formations have to be regarded as secon¬dary, though some of them probably include relicts of the primitive climax (WARMING, E. 2). On close examination, the Scrub cannot be considered as the climax, because of the following facts: 1. In the zone of Rain-Forest stretches of forest are present in very varied topographic conditions and the reconstitution of the associations show that man has destroyed an ecological unit (fig. 2). 2. In the zone of Scrub the characteristic patches are small. The banks of rivers and brooks, the valleys and ravine and whatever the soil has retained some humidity, is being invaded fry Rain Forest, which seems to be growing under optimum conditions. The Scrub is thus limited to small belts on the calcareous mountains and on sandy soils with alcaline depths (pH abo¬ve 7) which do not retain enough moisture for the Rain Forest that is progres¬sively restricting the area occupied by Scrub. In view of the topographic and present climatic conditions the Rain Forest must consequently be regarded as the regional climax. The presence of ecologically contradictory elements and associations shows that the real problem is that of the fluctuations of the climate of Passos or even of Minas Geraes during the quaternary and recent periods (DAN-SEREAU, P. : 3), a subject on which little is known and which is tied to the evolution of the climate of Brazil (OLIVEIRA, E. : 4) . The transformation of Scrub into Rain Forest has been - observed by the author before, in other parts of Brazil (VELOSO, PL P.: 5) . It seems probable that the Rio Grande has also greatly influenced the change of the regional vegetation, by invading areas of Scrub and dislocating the limit of the Pluvial climate towards the Canastra Range, though there are remnants of Scrub (postclimax) transfor¬med into secondary open country (disclimax, fig. 5) by human devastation and the setting of fire to the land. VEGETATION GROUPS OF THE PLUVIAL TYPE. The map of the region also shows that at the present time the small patches of forest (whether devasted or intact) occupy the least accessible places, such as valleys, peaks and abrupt slopes (fig. 2). Even these are now being destroyed, so that in the near future this forested region will be en¬tirely reduced to poor pasture land unless energetic measures of conservation are undertaken in time. The Special Service for Prophylaxis against Yellow Fever installed two of their four Stations for the Capture of Mosquitos in this area, one of them at Batatal and the other at Cachoeira, which have separate formations each of them composed of several associations. Other vegetation formations were also analysed, from the synecological point of view, so as to ascertain of which degree of succession their associations belong. These phytosociological sur¬veys give an idea of the principal characteristics of each station. BATATAL FORMATION. The abrupt nature of the valley has rendered this location inappropriate for agricultural purposes since colonial times. The relict of the primitive forest climax saved by this circumstance has expanded gradually to zones whose paedologic conditions favour the eatablishment of mesophilous species. The aerial photograph shows two small stretches of forest, one apparently primi¬tive, the other composed of associations belonging to the subclimax of the subsere. CACHOEIRA FORMATION. Aerial photographs show that this station is crossed by a small river, which divides it into two separate parts. The first, which presents ecological conditions similar, though not identical to those of Batatal, is favoured by topography and apparently remains primitive forest. Though the topography of the other, on the whole, favours the establishment of groups belonging to the normal sere of the climax, is has been partly devastated recently and the aspect of the associations has been completely modified. It was is this part that the four posts for the capturing of mosquitos were set up. The first forest is favoured by deposition of organic matter, washed out from the nearby devasted areas by torrential rains, and thus provides, an appropriate HABITAT for the climax species with certain hygrophilous trends of the ecological quasiclimax type. This association seems to have reached a biological equilibrium, as the dominates. Gallesia gorarema and Cariniana legalis (fig. 10), present an optimum vitality with a vigorous habit and a normal evolutionary cycle. The Cariniantum legalis Gallesiosum equilibrium, corresponds however, to a provisory association, because if the moving of soil by torrential rains should cease it would become possible…

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It is well known that the culture media used in the presumptive diagnosis of suspiciuous colonies from plates inoculated with stools for isolation of enteric organisms do not always correctly indicate the major groups of enterobacteria. In an effort to obtain a medium affording more exact indications, several media (1-9) have been tested. Modifications of some of these media have also been tested with the result that a satisfactory modification of Monteverde's medium was finaly selected. This proved to be most satisfactory, affording, as a result of only one inoculation, a complete series of basic indications. The modification involves changes in the formula, in the method of preparation and in the manner of storage. The formulae are: A. Thymol blue indicator: NaOH 0.1/N .............. 34.4 ml; Thymol blue .............. 1.6 g; Water .................... 65.6 ml. B. Andrade's indicator. C. Urea and sugar solution: Urea ..................... 20 g; Lactose ................... 30 g; Sucrose ................... 30 g; Water .................... 100 ml. The mixture (C.) should be warmed slightly in order to dissolve the ingredients rapidly. Sterilise by filtration (Seitz). Keep stock in refrigeratior. The modification of Monteverde's medium is prepared in two parts. Semi-solid part - Peptone (Difco) 2.0 g; NaCl 0.5 g; Agar 0.5 g; Water 100.0 ml. Boil to dissolve the ingredients. Adjust pH with NaOH to 7.3-7.4. Boil again for precipitation. Filter through cotton. Ad indicators "A" 0.3 ml and "B" 1.0 ml. Sterilise in autoclave 115ºC, 15 minutes in amounts not higher than 200 ml. Just before using, add solution "C" asseptically in amounts of 10 ml to 200 ml of the melted semi-solid medium, maintained at 48-50ºC. Solid part - Peptone (Difco) 1.5 g; Trypticase (BBL) 0.5 g; Agar 2.0 g; Water 100,00 ml. Boil to dissolve the ingredients. Adjust pH with NaOH to 7.3-7.4. Boils again. Filter through cotton. Add indicators "A" 0.3 ml and "B" 1.0 ml; ferrous ammonium sulfate 0.02 g; sodiun thiosulfate 0.02 g. Sterilise in autoclave 115ºC, 15 minutes in amounts not higher than 200 ml. Just before using, add solution "C" asseptically in amounts of 10 ml to 200 ml of the melted solid medium, maintained at 48-50ºC. Final medium - The semi-solid part is dispensed first (tubes about 12 x 120 mm) in 2.5 ml amounts and left to harden at room temperature, in vertical position. The solid part is dispensed over the hardened semi-solid one in amounts from 2.0 ml to 2.5 ml and left to harden in slant position, affording a butt of 12 to 15 mm. The tubes of medium should be subjected to a sterility test in the incubator, overnight. Tubes showing spontaneous gas bubbles (air) should then be discarded. The medium should be stored in the incubator (37ºC), for not more than 2 to 4 days. Storage of the tubes in the ice-box produces the absorption of air which is released as bubbles when the tubes are incubated at 37ºC after inoculation. This fact confirmed the observation of ARCHAMBAULT & McCRADY (10) who worked with liquid media and the aplication of their observation was found to be essential to the proper working conditions of this double-layer medium. Inoculation - The inoculation is made by means of a long straight needle, as is usually done on the triple sugar, but the needel should penetrate only to about half of the height of the semi-solid column. Indol detection - After inoculation, a strip of sterelized filter papaer previously moistened with Ehrlich's reagent, is suspended above the surface of the medium, being held between the cotton plug and the tube. Indications given - In addition to providing a mass of organisms on the slant for serological invetigations, the medium gives the following indications: 1. Acid from lactose and/or sucrose (red, of yellowsh with strains which reduce the indicators). 2. Gas from lactose and/or sucrose (bubbles). 3. H[2]S production, observed on the solid part (black). 4. Motility observed on the semi-solid part (tubidity). 5. Urease production, observed on solid and semi-solid parts (blue). 6. Indol production, observed on the strip of filter paper (red or purplish). Indol production is not observed with indol positive strains which rapidly acidify the surface o the slant, and the use of oxalic acid has proved to give less sensitive reaction (11). Reading of results - In most cases overnight incubation is enough; sometimes the reactions appear within only a few hours of incubation, affording a definitive orientation of the diagnosis. With some cultures it is necessary to observe the medium during 48 hours of incubation. A description showing typical differential reaction follows: Salmonella: Color of the medium unchanged, with blackening of the solid part when H[2]S is positive. The slant tends to alkalinity (greenish of bluish). Gas always absent. Indol negative. Motility positive or negative. Shigella: Color of the medium unchanged at the beginning of incubation period, but acquiring a red color when the strain is late lactose/sucrose positive. Slant tending to alkalinity (greenish or purplish). Indol positive or negative. Motility, gas and H[2]S always negative. Proteus: Color of the medium generally changes entirely to blue or sometimes to green (urease positive delayed), with blackening of solid part when H[2]S is positive. Motility positive of negative. Indol positive. Gas positive or negative. The strains which attack rapidly sucrose may give a yellow-greenish color to the medium. Sometimes the intense blue color of the medium renders difficult the reading of the H[2]S production. Escherichiae and Klebsiellae: Color of the medium red or yellow (acid) with great and rapid production of gas. Motility positive or negative. Indol generally impossible to observe. Paracoli: Those lactose of sucrose positive give the same reaction as Esherichia. Those lactose or sucrose negatives give the same reactions as Salmonellae. Sometimes indol positive and H[2]S negative. Pseudomonas: Color of the medium unchanged. The slant tends to alkalinity. It is impossible to observe motility because there is no growth in the bottom. Alkaligenes: Color of the medium unchanged. The slant tends to alkalinity. The medium does not alter the antigenic properties of the strains and with the mass of organisms on the slant we can make the serologic diagnosis. It is admitted that this medium is somewhat more laborious to prepare than others used for similar purposes. Nevertheless it can give informations generally obtained by two or three other media. Its use represents much saving in time, labor and material, and we suggest it for routine laboratory work in which a quick presumptive preliminary grouping of enteric organisms is needed.

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Aedes fluviatilis is susceptible to infection by Plasmodium gallinaceum and is a convenient insect host for the malaria parasite in countries where Aedees aegypti cannot be maintained in laboratories. In South America, for instance, the rearing of A. aegypti the main vector of urban yellow fever, is not advaisable because of the potential health hazard it represents. Our results of the comparative studies carried out between the sporogonic cycle produced with two lines of P. gallinaceum parasites into A. fuviatilis were as follows. As proved for A. aegypti, mosquito infection rates were variable when A. fluviatilis blood-fed on chicks infected with and old syringe-passaged strain of P. gallinaceum. Oocysts developed in 41% of those mosquitos and the mean peak of oocyst production was 56 per stomach. Salivary gland infections developed in about 6% of the mosquitos. The course of sporogony was unrelated to the size of the inoculum administered to chicks or to the route by which the birds were infected. The development of infected salivary glands was unrelated to oocyst production. Sporogony of P. gallinaceum was more uniform when mosquitos blood-fed on chicks infected with a sporozoite-passaged strain. Oocysts developed in about 50% of those mosquitoes and the mean peak of oocyst production was 138 per stomach, with some individuals having as many as 600-800 oocysts. Infected salivary glands developed in a mean of 27% of the mosquitos but, in some batches, was a high as 50%. Patterns of salivary gland parasitism were similar to those of oocyst production. The course of sporogony of P. gallinaceum in A. fluviatilis is analized in relation to degree of parasitemia and gametocytemia in the vertebrate host.

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A description of Physa marmorata Guilding, 1828, based on material collected at its type-locality, the Caribbean island of Saint Vincent, is presented. The shell is thin, horn-colored, surface very glossy, diaphanous. Spire acute, elevated; protoconch distinct, rounded-conical, reddish-brown; five not shouldered, broadly convex whorls with subobsolete spiral lines and thin growth lines. Aperture elongated, 1.4-2.0 times as long as the remaining shell length, narrow obovate-lunate; upper half acute-angled,lower half oval,narrowly rounded at the base, outer lip sharp, inner lip completely closing the umbilical region; a very distinct callus on the parietal wall; columellar lip with a low ridge gradually merging into the callus. ratios: shell width/shell length = 0.44 - 0.52 (mean 0.47); spire length /shell lenght = 0.33-0.41 (mean 0.39); aperture length/shell lenght = 0.59-0.67 (mean 0.62). Oral lappets laterally mucronate, foot spatulate with deeply pigmented acuminate tail. Mantle reflection with 6-10 short triangular dentations covering nearly half the right surface of the body whorl, and 4-6 covering a part of the ventral wall. Body surface with tiny dots of greenish-yellow pigment besides melanin. Renal tube tightly folded in toa zigzag course. Ovotestis diverticula acinous, laterally pressed against each other around a collecting canal. Ovispermiduct with well-developed seminal vesicle. oviduct highly convoluted, merging into a less convoluted nidamental gland which narrows to a funnel-shaped uterus and a short vagina. Spermathecal body oblong, more or less constricted in the middle and somewhat curved; spermathecal duct uniformly narrow, a little longer than be body. About 20 prostatic diverticula, simple, bifurcate or divided into a few short branches, distalmost ones assembled into a cluster. Penis long, nearly uniformly narrow; penial canal with lateral opening about the junction of its middle and lower thirds. Penial sheath with a bulbous terminal expasion the tip of which isinserted into the caudal end of the prepuce. Prepuce shouldered, much wider than the narrow portion of the penial sheath. Penial sheath/prepuce ratio about 2.08 (1.45-2.75). The main extrinsic muscles of the penial complex are a retractor, with a branch attached to the bulb, and another to the caudal end of the penial sheath; and a protractor, with a branch attached to the shoulder of the prepuce and adjoining area of the penial sheath, and another to the caudal end of the penial sheath. Egg capsule C-shaped, with 10-30 elliptical eggs (snails 10mm long) measuring about 1.10 mm (0.90-1.32) through the long axis and surrounded by an inner and an outer lamellate membranes. Jaw a simple obtusely V-shaped plate. radula will be described separately.

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Mosquitoes are vector of serious human and animal diseases, such as malaria, dengue, yellow fever, among others. The use of biological control agents has provide an environmentally safe and highly specific alternative to the use of chemical insecticides in the control of vector borne diseases. Bacillus thuringiensis and B. sphaericus produce toxic proteins to mosquito larvae. Great progress has been made on the biochemical and molecular characterization of such proteins and the genes encoding them. Nevertheless, the low residuality of these biological insecticides is one of the major drawbacks. This article present some interesting aspects of the mosquito larvae feeding habits and review the attempts that have been made to genetically engineer microorganisms that while are used by mosquito larvae as a food source should express the Bacillus toxin genes in order to improve the residuality and stability in the mosquito breeding ponds.

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We show here a simplified reverse transcription-polymerase chain reaction (RT-PCR) for identification of dengue type 2 virus. Three dengue type 2 virus strains, isolated from Brazilian patients, and yellow fever vaccine 17DD, as a negative control, were used in this study. C6/36 cells were infected with the virus, and tissue culture fluids were collected after 7 days of infection period. The RT-PCR, a combination of RT and PCR done after a single addition of reagents in a single reaction vessel was carried out following a digestion of virus with 1% Nonidet P-40. The 50ml assay reaction mixture included 50 pmol of a dengue type 2 specific primer pair amplifying a 210 base pair sequence of the envelope protein gene, 0.1 mM of the four deoxynucleoside triphosphates, 7.5U of reverse transcriptase, and 1U of thermostable Taq DNA polymerase. The reagent mixture was incubated for 15 min at 37oC for RT followed by a variable amount of cycles of two-step PCR amplification (92oC for 60 sec, 53oC for 60 sec) with slow temperature increment. The PCR products were subjected to 1.7% agarose gel electrophoresis and visualized with UV light after gel incubation in ethidium bromide solution. DNA bands were observed after 25 and 30 cycles of PCR. Virus amount as low as 102.8 TCID50/ml was detected by RT-PCR. Specific DNA amplification was observed with the three dengue type 2 strains. This assay has advantages compared to other RT-PCRs: it avoids laborious extraction of virus RNA; the combination of RT and PCR reduces assay time, facilitates the performance and reduces risk of contamination; the two-step PCR cycle produces a clear DNA amplification, saves assay time and simplifies the technique

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Cemeteries with many water-filled containers, flowers, sources of human blood, and shade are favorable urban habitats for the proliferation of Aedes aegypti, a vector of yellow fever and dengue. A total of 22,956 containers was examined in the five cemeteries of the city of Buenos Aires, Argentina. The vector was found in four cemeteries that showed an average infestation level of 5.5% (617 positive out of 11,196 water-filled containers). The four cemeteries positive for Ae. aegypti showed significantly different (p<0.01) infestation levels. Vegetation cover and percentage of infestation were significantly correlated (p<0.01), but neither cemetery area nor number of available containers were significantly related to the proportion of positive vases. Our results suggest that the cemeteries of Buenos Aires represent a gradient of habitat favorableness for this vector species, some of which may act as foci for its proliferation and dispersal.

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Hepatic viscerotomy of paraffin-preserved old specimens, collected in the period from 1934 to 1967, were analyzed by immunohistochemical assays to detect hepatitis B, hepatitis D, dengue and yellow fever virus antigens. The material belongs to the Yellow Fever Collection, Department of Pathology, Instituto Oswaldo Cruz, Rio de Janeiro, Brazil and the cases were diagnosed at that time according to clinical aspects and histopathological findings reporting viral hepatitis, yellow fever, focal necrosis and hepatic atrophy. From the 79 specimens, 69 were collected at the Labrea Region and the other 10 in different other localities in the Amazon Region. The five micra thick histological slices were analyzed for the presence of hepatitis B surface antigen (HBsAg) and hepatitis B core antigen (HBcAg) by immunoperoxidase technique. An immunofluorescence assay was applied to the detection of hepatitis D, yellow fever and dengue virus antigens. Nine (11.4%) histological samples were HBsAg reactive and 5 (6.3%) were HBcAg reactive. The oldest reactive sample was from 1934. Viral antigens related to the other pathologies were not detected in this study. Our results confirm that the methodology described may be used to elucidate the aetiology of hepatitis diseases even after a long time of conservation of the specimens.

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In this work, a comprehensive phylogenetic study based on 600 base pair nucleotide and on putative 200 amino acid sequences of NS5 was carried out in order to establish genetic relationships among 15 strains of 10 Brazilian flaviviruses: Bussuquara, Cacipacore, dengue type 1, 2 and 4, Iguape, Ilheus, Rocio, Saint Louis encephalitis (SLE), and yellow fever. Phylogenetic trees were created by neighbor-joining and maximum parsimony methods. These trees showed Brazilian flaviviruses grouped into three main branches: yellow fever branch, dengue branch subdivided in types 1, 2 and 4 branches, and Japanese encephalitis virus (JEV) complex branch including SLE virus strains, Cacipacore, Iguape, Rocio, Ilheus and Bussuquara. Viruses transmitted by Aedes mosquitoes, such as dengue and urban yellow fever, that are also the only Flavivirus causing hemorrhagic fevers in Brazil, were grouped in the same cluster. Encephalitis associated viruses, transmitted by Culex mosquitoes such as JEV complex branch including SLE virus strains, Cacipacore, Iguape, Rocio, Ilheus and Bussuquara were also grouped in the same clade.

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An impressive array of cellular and molecular adaptive responses achieves homeostasis. The inflammatory reaction is an adaptive response triggered by an insult to culminate into the overt cardinal signs of inflammation, eventually leading to resolution and returning the organism back to its original centered state. This article focuses on some aspects of the lipoxin A4 signaling pathway during the resolution phase, to better understand molecular mechanisms by which a neutrophil directs an inflammatory reaction to switch off and resume homeostasis. Defining the resolution state of a neutrophil at the molecular level will aid in treatments of diseases that are associated with an exaggerated and uncontrolled inflammation.

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Recent advances in basic science pointed to a role for proteinases, through the activation of proteinase-activated receptors (PARs) in nociceptive mechanisms. Activation of PAR1, PAR2 and PAR4 either by proteinases or by selective agonists causes inflammation inducing most of the cardinal signs of inflammation: swelling, redness, and pain. Sub-inflammatory doses of PAR2 agonist still induced hyperalgesia and allodynia while PAR2 has been shown to be implicated in the generation of hyperalgesia in different inflammatory models. In contrast, sub-inflammatory doses of PAR1 increases nociceptive threshold, inhibiting inflammatory hyperalgesia, thereby acting as an analgesic agent. PARs are present and functional on sensory neurons, where they participate either directly or indirectly to the transmission and/or inhibition of nociceptive messages. Taken together, the results discussed in this review highlight proteinases as signaling molecules to sensory nerves. We need to consider proteinases and the receptors that are activated by proteinases as important potential targets for the development of analgesic drugs in the treatment of inflammatory pain.